Leo Fitz

"You make things from the genius of your mind and the goodness of your heart to help people. Don't let Radcliffe's actions corrupt that. You are not responsible for the twisted things he's done."

- Jemma Simmons to Leo Fitz

Leopold James "Leo" Fitz is a Scottish-born S.H.I.E.L.D. agent and scientist. A genius, he is one of the youngest and most prominent members of S.H.I.E.L.D.'s Sci-Tech division, and inseparable from his research partner and friend (and later girlfriend), Jemma Simmons. He, along with Simmons, was recruited to Coulson's Team and worked with them on all of their missions. While on the team, Fitz became good friends with teammates Grant Ward and Skye. During the HYDRA Uprising, Fitz was an active participant in hunting for John Garrett and the rest of the Centipede Project. He was shocked by the revelation that Ward had been a member of HYDRA all along, and refused to believe it. When Ward was ordered to kill him and Simmons, they were trapped on the ocean floor. They escaped, but Fitz spent a long period of time without oxygen, causing brain damage.

As time progressed, Fitz's condition seemed to get better with help and support from his fellow S.H.I.E.L.D. colleagues rebuilding it. Slowly regaining his skills, Fitz was able to get back into doing active field and lab work, and played an important role in the conflicts with Robert Gonzales' S.H.I.E.L.D. faction and during the War against the Inhumans, in which he caused the death of teleporter Gordon. However, soon after the war was over, Simmons was swallowed by the Monolith and disappeared.

Fitz studied the Monolith for months and with S.H.I.E.L.D.'s help, he went through a portal to a distant planet and rescued her. Even with Simmons's return, Fitz was devastated to learn she had met and bonded with the astronaut Will Daniels. Fitz helped Simmons research a way back to the planet, but their work attracted the attention of HYDRA, which forced Fitz go back to the planet to bring their Inhuman leader home. There, Fitz learned that Daniels had died and his body was possessed by the dark Inhuman. Fitz destroyed Daniels' body and returned home, believing the Inhuman was dead. However, the dark Inhuman, Hive, managed to return to Earth. Fitz and Simmons, having become a couple meantime, tried to find a cure to Hive's power of controlling Inhumans' minds. S.H.I.E.L.D. eventually managed to kill Hive.

S.H.I.E.L.D. had its new Director after the signing of the Sokovia Accords. Fitz worked with Dr. Holden Radcliffe on developing an Artificial Intelligence called Aida which was designed to serve S.H.I.E.L.D. as a decoy target. He was caught in an explosion with Coulson and Ghost Rider by Eli Morrow and was almost sent into another dimension, but managed to get out. Fitz then helped S.H.I.E.L.D. in their last fight against Morrow. To Fitz's shock, Radcliffe betrayed S.H.I.E.L.D. and used Fitz's technology against S.H.I.E.L.D.. Fitz was captured and his mind was connected to the virtual reality called the Framework where he lived a rewritten life as The Doctor, Aida's lover and HYDRA's ruthless second-in-command.

Early Life
Leopold Fitz was born in Scotland, United Kingdom on Wednesday, August 19, 1987. A genius-level engineer, whose only other relative is his mother, after his father, Alistair Fitz, left him at age 10. Leo Fitz started attending the S.H.I.E.L.D. Academy of Science and Technology in 2004, where he met who would become his equally intelligent best friend, bio-chem expert Jemma Simmons. Among their instructors at the academy were Professor Vaughn and chemical kinetics advisor, Professor Franklin Hall.

Fitz and Simmons graduated from the academy three years early, and Fitz would have been happy to spend all of his time in a lab. However, at the urging of Simmons (and against the advice of Professor Vaughn), the pair put in for a field position.

First Missions for Coulson's Team
"I said there would come a moment when we would regret the decision to go in the field. I didn't think that would happen in week one."

- Leo Fitz to Jemma Simmons

Fitz and Simmons were recruited by Agent Phil Coulson to be the science crew for a new team he was putting together. Stationed on the Bus, the pair have designed specialized equipment and compounds on the fly in emergency situations.

Their first foray into the field involved the case of Michael Peterson, a man in danger of exploding due to his use of the volatile Centipede Serum. Peterson was saved in part by Fitz's invention, the Night-Night Gun, which contained specially designed bullets that delivered a Centipede counter-agent to Peterson.

Fitz first faced danger in the field in Peru, where the team was investigating an 0-8-4. Facing Peruvian rebels and an armed takeover of the Bus, Fitz found it hard to concentrate at first, but later came through for the team, using his D.W.A.R.F.s to activate the old HYDRA weapon in order to regain control of the Bus. The team received a call that a S.H.I.E.L.D. truck was attacked. They arrived to investigate, and it was discovered that a mysterious new element was distorting gravity and throwing the vehicles in the air. The team learned that the cargo in the truck was in fact Fitz' and Simmons' former professor Franklin Hall, who had been captured by Ian Quinn. Coulson, Ward, and Skye infiltrated the billionaire's home in an attempt to rescue Hall, but despite Fitz' and Simmons' attempts to convince Coulson that Hall was a good man, Coulson was forced to kill Hall when he tried to destroy the entire island and kill every person on it. Their next mission had them investigating mysterious dead bodies which floated in the air. As a team they discovered that the cause was an virus passed along from a Chitauri Helmet. On the way back on the Bus, it was discovered that Simmons was infected and would be killed in a matter of hours unless they found a cure. Fitz risked contamination and death in order to help save his friend and they successfully found a cure.

However Simmons, not realizing the cure worked, chose to jump from the plane to save the rest of the crew. Fitz took the cure and prepared to jump out after her, but instead Grant Ward jumped and saved her life. Later, they sat together and Simmons expressed her gratitude to her friend.

Operation: Overkill
"I am every bit the S.H.I.E.L.D. agent you are!"

- Leo Fitz to Grant Ward

Sometime later, Fitz and Agent Grant Ward were assigned by Agent Victoria Hand to infiltrate the border of South Ossetia and destroy an enemy weapon known as the "Overkill Device". Despite his inexperience (and a few missteps), Fitz showed quick thinking, ingenuity and courage during the assignment and was essential to the successful completion of the mission.

Agent Fitz' noteworthy actions include the timely activation of a Localized EMP Device when his and Agent Ward's lives were in jeopardy, gaining the trust of the locals (specifically Marta and Vladimi) and the modification of the Overkill Device's core, which allowed him to neutralize the enemy soldiers weapons.

Among his missteps were the vastly overpaying the locals for safe transit across the border and bringing a sandwich (prosciutto and buffalo mozzarella with a hint of pesto aioli) into the field while being tracked by dogs.

The Berserker Staff
In Trillemarka National Park, Fitz assisted Simmons in creating a 3D model of the recently discovered fragment of the Berserker Staff. Simmons scanned the imprint of the staff in the tree where it was previously embedded, while Fitz worked to create a replica back in the lab.

After Grant Ward came into contact with the Berserker Staff, he became unnaturally aggressive toward his teammates, with Fitz being one of them. Ward delivered a harsh rebuttal to the suggestion of sedation by mocking Fitz, reminding Fitz that he had been the one to save Simmons after she contracted the Chitauri Virus. Fitz seemingly ignored the comment.

Later, in a church in Oslo, Elliot Randolph was brutally stabbed with a fragment of the staff. While Simmons realized she couldn't help save his inhuman life, Fitz supported her by reminding Coulson that she didn't understand Randolph's anatomy. After Simmons saved Randolph with the help of Coulson, Fitz comforted her when she was disappointed in herself for not being brave enough. Relenting in his comfort, Simmons spoke with her parents on the phone, a task she had been procrastinating.

Hunting a Ghost
Fitz and Jemma Simmons traveled to the StatiCorp company to gather information concerning the tragic accident that had occurred there. While on the job, the two reminisced on being victims of freshman pranks back at the S.H.I.E.L.D. Academy. Realizing Skye was a "freshman" to S.H.I.E.L.D., they decided to "give her the full S.H.I.E.L.D. experience". This commenced to a series of pranks they planned to pull on Skye. Later, Coulson's Team took possession of Hannah Hutchins, the young woman being held responsible for the accident. As Fitz entered a closet for prank supplies and couplings, he was mysteriously locked inside and the plane lost power and went down, courtesy of Tobias Ford. Fitz soon escaped the closet and met up with the rest of the team, and went to repair the damage that had been done to the plane's wiring system. He successfully got them up and running again.

Late that night, Fitz had been sleeping peacefully while Coulson, Ward, Skye, and Simmons played "Upwords" in the lounge. He silently entered the room, with shaving cream smeared across his face. He became irritated as the team laughed at his misfortune, and he demanded to know who was responsible, completely unaware of Melinda May's guilt in the prank.

Coulson's Capture
Fitz watched helplessly with the rest of the team as Phil Coulson was captured by Raina and the Centipede Project. He and Simmons had created a tech-free method of tracking Mike Peterson, but never thought to do the same for Coulson.

Once the team had returned to the Bus, Fitz witnessed Victoria Hand kick Skye off the plane. In any and all assistance he could provide, he and Simmons hid supplies for Skye in a paper lunch sack, including a SAT phone for her to reach them. In the lab, Fitz designed a new weapon using Night-Night Gun technology, which he called the Night-Night Bracelet. The bracelet later proved to be impractical in a fight. Later, in the desert where Coulson was being tortured by Edison Po, Fitz fought alongside his team to find Coulson and keep each other safe. They managed to get Coulson out, and they all reached the Bus; not unscathed, but alive. Fitz shared a warm moment with Coulson, a sign of appreciation for rescuing him.

Bad Seeds
Coulson's Team received a report of a mysterious attack at the S.H.I.E.L.D. Academy of Science and Technology. The incident involved an indoor pool instantly being frozen, with young cadets in it. The team made a visit, and Leo Fitz and Jemma Simmons, being very well known in the academy, prepared a speech to share their experiences in the field with the students. However, in the middle of their speech, a student began to cry in panic, as his body was being slowly frozen over. Fitz and Simmons rushed to the cadet, with Grant Ward and Skye alongside them. Simmons administered a drug to keep the boy alive, and Ward located a machine that was the source of the ice. Upon Fitz's orders, the machine was smashed, and the student, later revealed to be Donnie Gill, was saved. Gill briefly thanked Fitz and Simmons for saving him, and apologized for ruining their speech. He was then escorted back to his dorm to recover.

On Ward's suggestion, Fitz visited Gill in his dorm, and the two instantly connected. Fitz admired Gill's inventions and designs and he shared stories of himself at the academy and how he did not like it there at first either. He and Gill bonded over common experiences. Eventually, Fitz took note of a power problem Gill was having. He suggested to him a solution and Gill immediately realized his problem was solved.

Fitz bid goodbye to Gill and began to head to the Boiler Room of the Academy at Simmons' request. Simmons told him distressing news over the phone, that everything was not as it seemed, and Fitz rushed back to Gill's dorm. There, he discovered an upscale version of the freezing device found earlier, and frantically warned Gill of the danger. Since Fitz had seen too much, Seth Dormer, a friend of Gill's, shot the engineer unconscious. Fitz was removed from the situation, and received news that Gill's weather machine had gone haywire, causing a massive storm. The team located the source, along with Gill and Dormer, and brought them on board the Bus, seeing as Dormer was injured. He had been struck by lightning, and despite Simmons' efforts, he did not survive. Fitz tried to comfort the grieving Gill, but was pushed away.

The Chase
Fitz was captured in France and taken to Antarctica. The team rescued him and destroyed the outpost that held him.

The Italian Mission
Fitz was forced out of his niche and into field work when the team got separated during a mission in Italy where they were chasing a Cybertek Prosthetic Leg bought by Ian Quinn. He and Skye were the only ones left who could continue the chase. As Fitz waited for the others after he sent a tracking beacon, Skye went inside Quinn's mansion and was shot twice in the stomach.

Fitz blamed himself for this as the team went to S.H.I.E.L.D. Trauma Zentrum in Switzerland, and learned that Skye's wounds were fatal. Phil Coulson refused to accept this diagnosis and gave him and Jemma Simmons Level 10 access to files on his resurrection. Fitz figured out the location of the Guest House and went with Coulson, Grant Ward and John Garrett to find GH.325. After a successful Raid of the Guest House, Fitz took the serum to Skye for Simmons to inject her with it, fully healing his teammate.

Secrets
Unfortunately, that was the only sample he retrieved and Jemma Simmons berated him for it because the Guest House was destroyed. He and Simmons continuously monitored Skye and took blood samples in hopes of duplicating the miracle drug, but the Bus did not have equipment sufficient enough for the job. Also, Phil Coulson ordered the research must stay in house. Meanwhile, Lorelei and Grant Ward hijacked the Bus and enthralled Fitz. Simmons began to look at him differently.

Fitz witnessed as Skye became an official S.H.I.E.L.D. agent and watched as Ward killed Thomas Nash. He became upset though as Simmons was called to the Hub to be a consultant on Deathlok. So they could communicate secretly about her findings on GH.325, Fitz put in a secret phone line. However, he found that Melinda May already had one. He told Skye about this just as it was realized that the Clairvoyant was a S.H.I.E.L.D. agent. May chased Fitz hoping to shoot him with an I.C.E.R. before he could reveal her secret, but he locked himself away before she found him. While Phil Coulson, May, Skye, and Fitz had a four-way argument about secrets, Victoria Hand redirected the Bus to kill Coulson's Team.

HYDRA Uprising
"You're going to suffer for what you've done. And I- I plan to be a very big part of that."

- Leo Fitz to John Garrett

Fitz watched Phil Coulson and John Garrett battle the S.H.I.E.L.D. UAVs chasing Garrett as it became assumed that Victoria Hand was the Clairvoyant. When they reached the Hub, Fitz's invention, the Mouse Hole, kept them from being captured. Garrett accidentally revealed he was the Clairvoyant and an agent of HYDRA, greatly upsetting Fitz for his betrayal. Garrett offered Fitz a place in HYDRA while Fitz swore vengeance. During the Battle at the Hub, Fitz hid but his contributions saved his teammates' lives when it was needed.

Fitz began to notice the attraction Jemma Simmons had for Antoine Triplett, but he distrusted him since he worked under Garrett. When the team and Triplett left the Hub to go to Providence, Fitz talked with Simmons, but she let him know that things have changed.

Fitz went with Phil Coulson, Triplett and Simmons to Portland to apprehend Blackout. He discovered Coulson's past relationship with Audrey Nathan, and talked Coulson into using her as bait to stop the Fridge escapee. Fitz modified the stage lights of the building using the Gamma Power Reserve designed by Bruce Banner causing Blackout to explode. When the group returned to Providence, they found the Bus and half the team gone.

Betrayed
"Ward look at me, Ward just turn around. I know that you care about us Ward!" "You're right, I do, it's a weakness."

- Leo Fitz and Grant Ward

Fitz helped Coulson research their whereabouts, but he questioned Coulson's leadership after their experiences in Portland. Looking for a skillet to help Simmons make pancakes, Fitz found a message left by Skye, "Ward is HYDRA," just as Simmons found Agent Eric Koenig's body. When Simmons' autopsy report proved Ward was the killer, Fitz had a tantrum that had to be calmed by Coulson. Meanwhile, Maria Hill led Colonel Glenn Talbot to Providence, causing Fitz and the team to relocate to Los Angeles. During this time, he refused to believe that Ward was evil, claiming that he did not think that people were born evil. He even suggested the possibility that Ward was like Deathlok and was forced to do what he did, but his teammates dismissed the idea. Eventually, Coulson's Team found John Garrett and Grant Ward in Havana, Cuba. Fitz and Simmons were able to locate the Bus, and Coulson ordered them to leave the area immediately. As they were about to, Fitz and Simmons decided to plant a tracking device on the Bus. Just then, Ward found the two as Centipede Project prepared to leave for New Mexico. He brought Fitz and Simmons aboard the Bus where Fitz activated an EMP Joy Buzzer that critically injured Garrett. Fitz begged Ward to let Garrett die, telling him that he did not have to follow Garrett. Garrett then told Ward to kill Fitz and Simmons. As they were being escorted away by guards, Fitz and Simmons managed to escape their guards, but Ward found them, resulting in a chase. Cornered, Fitz and Simmons then locked themselves into a Medical Pod. Ward demanded that the two come out, but they refused. Fitz reminded Ward of their friendship and told Ward that he knew that Ward still cared about his team. Ward finally admitted that he still did, but he called it "a weakness" and ejected the pod off the bus into the Atlantic Ocean.

Best Friends Forever
"Why would you make me do this? You're my best friend in the world!" "You're more than that, Jemma."

- Jemma Simmons and Leo Fitz

Now trapped with Simmons on the seabed 90 feet down, Fitz jury-rigged a beacon transmitting a distress signal on an unmonitored S.H.I.E.L.D. frequency, all with a broken arm. When Simmons woke up, he explained the situation to her: there was no way out of the container, and they were going to die.

However, some time later, Simmons devised a way to break the glass keeping out the water. With some hope of escape, the pair worked out the problem further. Eventually, with the detonation ready to go, Fitz handed Simmons a one-time use air supply and explained that there wouldn't be enough for the both of them. After a tearful display of affection from Simmons, Fitz hit the trigger for the explosion. Not willing to give up her closest friend, Simmons dragged Fitz with her to the surface where they were rescued by the timely arrival of Nick Fury, responding to their makeshift distress signal. While Simmons was placed in a Hyperbaric Chamber to recover from the pressure sickness, Fitz was examined by a medical team. His brain went without oxygen for an extended period of time, although his heart was still beating.

Fitz ultimately survived the ordeal. However, when asked about him later, the fully recovered Simmons would only say "he's alive" with no further context, implying that Fitz suffered brain damage from oxygen deprivation.

Brain Damage
"What's the word again? Gimme the word."

- Leo Fitz

It took nine days for Fitz to awaken from his coma, but months later Fitz still experienced damage to parts of his brain that still had not healed. The brain injury made it difficult for Fitz to complete tasks that used to come easy to him and gave him, which made communicating to other members of the team much more difficult for him. Jemma Simmons left Fitz and the rest of the team to go undercover within HYDRA for S.H.I.E.L.D. After Simmons had left, he started to imagine she was still with him and had conversations with his hallucination of her. Eventually, Fitz realized that Simmons had left but continued to have the hallucinations.

Phil Coulson tasked him with building cloaking technology for the Bus so that he and his agents could travel unimpeded by Glenn Talbot and the United States government. Ultimately, Coulson sent Melinda May, Antoine Triplett, and Skye to steal a Quinjet when he deemed that Fitz was incapable of the job. However, Fitz was able to recognize the designs he had previously done on the Overkill Device as a way to disrupt Carl Creel's powers and cause him to overload. With the help of Alphonso Mackenzie, who took his time to help Fitz explain his thoughts, he was able to modify it in order to stop Creel, who was turned to stone and arrested. This cooperation started a friendship and strong trust between the two as Mackenzie was the only person who was really able to listen and took the time to speak to Fitz.

Meeting Ward
"I - I have trouble with words, so it might be best I show you." "Show me what?" "Hypoxia, that's what you did to me."

- Fitz and Grant Ward

Phil Coulson had a meeting with the field agents, included Leo Fitz, after he spoke with Jemma Simmons, who was undercover, infiltrating HYDRA. Fitz knew Donnie Gill from the mission at the S.H.I.E.L.D. Academy and Coulson sought his input. Fitz became upset that he was not leaving for Morocco with the others. He went to the Vault D and discovered that it held Grant Ward, who was happy to see Fitz again. Ward attempted to convince Fitz that he did not want to kill Fitz and Simmons, so he instead ejected their pod into the ocean to give them "a fighting chance" at survival. Fitz then revealed to Ward how brain damaged he was and that he now felt useless to his team, who he revealed were now in Morocco to look for Donnie Gill. Fitz slowly lowered the oxygen level of the cell to show Ward what he experienced. Suffocating, Ward told Fitz of how HYDRA brainwashed some of its members, including Gill, who had taken over the Sandbox while brainwashed. Fitz, with extreme difficulty due to his aphasia, was able to communicate this knowledge to Mack, and the two informed Coulson about this. When Coulson asked how Fitz knew this, Fitz admitted that Ward told him.

Coulson met with Fitz privately after this incident and expressed his regrets that he still had Ward at the base. Fitz asked if Coulson was hiding any other secrets from him, to which Coulson replied that as director of S.H.I.E.L.D., there were a lot of things that he was not telling Fitz, but he added that this was not just to Fitz. He also let Fitz know that Simmons left S.H.I.E.L.D. upon Coulson's request.

Bonding with the Others
"Fitz, this team wouldn't be here if it weren't for you. This is big. Let me buy you a beer, mate."

- Lance Hunter

The S.H.I.E.L.D. agents took the Bus to Florida because Phil Coulson wanted a painting that had the Words of Creation inscribed on its back. While the others were bonding, discussing past relationships and love interests, Fitz was hesitant because he felt that the others did not want to be around him since he had trouble speaking. His hallucination of Jemma Simmons kept trying to encourage him, but he refused. He also believed that the others talked to Ward more than they did to him, feeling that the others found Ward more useful.

Agent 33, disguised as Melinda May, entered the Bus and planted a virus which disrupted the electrical systems. Fitz warned the others that if the virus continued the plane would explode. He and Lance Hunter went to a section of the plane that was not yet affected. Fitz explained that he needed Hunter's hands, since his were not steady, to halt the cascading effect. Together, they rewired the section and stopped the virus.

Later, Hunter brought some alcohol to celebrate a successful mission. After prodding from Hunter, who wanted to thank Fitz for saving their lives, Fitz decided to participate and began talking about a girl, without saying that it was Simmons, not returning his feelings and leaving him. Alphonso Mackenzie and Hunter said he was better off without her and toasted to "moving on."

Soon after, Fitz let go of the imaginary Jemma, when the real Jemma Simmons returned from her undercover mission. Fitz greeted her with hesitancy.

Reunion with Simmons
Fitz and Simmons discussed the specifics of the HYDRA Splinter Bombs as well as Fitz's situation which led to a brief argument between them. Mack then came to discuss the specifics with Fitz which led to the discovery that Vincent Beckers, the grandfather of the Belgian Foreign Minister, was in fact a HYDRA agent in the 1940s who developed the weapon. Fitz later had a brief amiable conversation with Simmons. When Mack and Simmons spoke of Fitz's predicament, he pointed to her as the cause of his trouble to which she cited as the reason why she had left.

Mental Back-Up
Fitz went with Alphonso Mackenzie and they retrieved the body of Janice Robbins so Jemma Simmons could perform an autopsy. She disagreed with the words of bravado that Mack told Fitz. Fitz and Mack were told by Skye to come to the secret room containing the Theta Brain-Wave Frequency Machine; their strength might be needed in case Phil Coulson acted erratically during or after the session. As predicted, Coulson had to be held down after the session ended.

As Mack and Fitz played video games, because, according to Mack, playing helped Fitz's brain. Mack complained about how Coulson's brain was erased. Fitz explained that memories cannot truly be erased, as the brain makes back-up files that Coulson was accessing. During their conversation, Simmons entered and showed them Skye locked in Vault D.

Later, Fitz was among the senior agents that were assembled as Director Coulson gave the new mission: find the city that matched the Words of Creation before HYDRA can.

Muscle Memory
Wanting to return to field work, Fitz accompanied Skye and Antoine Triplett when Director Coulson took them to Hawaii. Coulson ordered Fitz to practice on the Bus rebuilding a transceiver repetitively until he can do it under six minutes. Fitz admitted that he had only one fully functional hand. Coulson told him to rely on muscle memory.

When the Bus got to Laura Creek, Australia, Coulson took Fitz and Triplett with him to infiltrate a laboratory that housed a powerful satellite receiving station. Fitz's job was to install the transceiver so that the city matching the Words of Creation could be found. Fitz admitted that he was able to do the job in under seven and half minutes, not six, when using one hand. He then revealed that with both his hands, he would be able to do the job within the time limit, signifying his progress. The team entered the station. There they were attacked by HYDRA and Triplett got shot.

Calvin Zabo helped Triplett but used that firefight as a way to meet Coulson. As he fled, Coulson and Fitz gave Triplett the blood clotting agents needed to stop him from bleeding to death. Before they could tell Skye about meeting her father, a match was found.

Relinquishing Leadership
When he returned to the Playground, Fitz saw Mack driving a radio-controlled miniature version of Lola through the halls. Fitz, wondering if the toy could fly, asked Mack to talk to Jemma Simmons for him. Mack told him that he needed to confront her sooner or later. Fitz was chosen to accompany Phil Coulson to Puerto Rico to destroy the city that matched the Words of Creation. The team also included Bobbi Morse, Mack, and Simmons. Upon arrival, the silence between the two scientists caused Mack to leave them alone so they could talk. As Simmons tearfully tried to tell Fitz why she left and went undercover months ago, Fitz interrupted her by saying that he could not work with her anymore. She misinterpreted his statement and asked if he was quitting S.H.I.E.L.D. He told her that he thought it best for him to work for her, making her leader of the science team.

Inside Castillo San Cristóbal, Fitz and Simmons prepared the D.W.A.R.F.s to test the structural integrity of the city, so when it was destroyed, it would not affect the residents of San Juan. When the drones lost power after entering a hundred foot shaft, Mack went down to investigate. Hearing his screams, the others hoisted him up and watched as he slapped Coulson across the room. Fitz gave Coulson an I.C.E.R. to stop the attack of the super-strong mechanic, but it was ineffective. Fitz, holding a gun, pleaded with his friend to stop his assault, while Coulson, attempting to keep Simmons from falling into the shaft, ordered him to fire. He did not because Morse electrocuted Mackenzie and he fell stunned into the shaft.

Kree City
Fitz and Simmons brainstormed on how to save Alphonso Mackenzie and destroy the city when they entered the Bus. Together, they decided that the city was like a living organism that co-opted Mack to have him defend it and that hazmat suits would keep the city from detecting their presence.

Antoine Triplett was partnered with them to destroy the city with the four mechanical bombs he had. Inside the Kree City, Fitz decided that for expediency, they needed to separate to set the charges. After the charges were set, Fitz witnessed as Triplett reported to Melinda May that their task was complete. Triplett immediately returned to the city to defuse the bombs when they learned that Skye and Phil Coulson entered.

As Fitz waited with Simmons, an earthquake occurred; this caused them to hug in panic as the island shook.

Empathy
"You're just different now and there's nothing wrong with that."

- Leo Fitz

Upon return from Kree City, the senior agents dealt with the experiences differently. Fitz helped Alphonso Mackenzie with his work. Soon, Fitz found work for himself; he decided to repair and analyze Skye's heart monitor to get a biological replay of what happened to her. While working, Fitz asked Mack to share his feeling about his experiences as a thrall of the Kree City. Mack shouted at Fitz, claiming that he could not understand the feeling of having his body betray him. Fitz calmly stated that he could due to his own brain damage.

Later, Fitz approached Skye in her quarantine. He began questioning the data he learned from the heart monitor, which he called "inhuman", as well as how she was unaffected by the earthquake. When he realized that she was the epicenter, Skye panicked and caused the overhead lamp to explode. Fitz ran away quickly. Fitz returned when Melinda May and Jemma Simmons saw Skye cut and bleeding. As Skye was about to admit that she was changed, Fitz interrupted her and showed the women Skye's blood test; he had changed the results to have it show that Skye was normal. When the women left, Fitz cleaned Skye's wound, explaining that until everyone has calmed down from their traumatic experiences, especially Simmons, who wanted to destroy all things alien, it was best to keep her secret between them. Skye cried and hugged Fitz. He told her that there was nothing wrong with being different.

Fitz attended the vigil the senior agents had for Antoine Triplett.

Secrets Exposed
While continuing the search for Raina, S.H.I.E.L.D. took notice of Lady Sif, who had appeared in Portugal with no recollection of her past or why she was on Earth. They discovered that Sif had fought an unknown man who wiped her memory with a hammer-like device. Following a confrontation with the man, Skye began to fear more that control over her abilities was wavering. She confided in Fitz, thinking that telling Phil Coulson about her new ability would be best; Fitz revealed that he was talking to hallucinations of Jemma Simmons for months. When Skye stared at Fitz, he told her that that feeling would be how the others would treat her. He then attempted to ease her mind, though they were interrupted by Lance Hunter.

Upon locating the man, who was revealed to be a Kree by the name of Vin-Tak, and bringing him in for questioning, the Kree restored Sif's memory and explained that he had come to Earth after being alerted to Raina's activation of a Diviner. Fitz and Jemma Simmons opened a crate Vin-Tak unearthed that supposedly had more Diviners; during which Fitz had inadvertently left his test results of Skye's blood out for Simmons to see. He attempted to explain that they were just fake results he created; however, Simmons was not completely convinced. Meanwhile, Vin-Tak explained the purpose of the Diviners, and the Kree's role in the creation of the Inhumans. Realizing that she was in fact one of these people, Skye began to panic and lost control of her powers, exposing them to her friends. Both Sif and Vin-Tak were ready to strike down Skye in order to stop her supposed threat, but Fitz, having overheard, was quick to come to Skye's defense, furious at their suggestion of murdering her. Both Coulson and May defended Skye as well and attempted to get her to safety. Coulson told Fitz to get "Bambino." While running, he came across Alphonso Mackenzie and Bobbi Morse, and urged them to help stop the Kree. Mack, and later Hunter, were quickly defeated; but Morse managed to keep Vin-Tak busy enough for Fitz to locate the Destroyer Armor Prototype Gun. The blast stunned Vin-Tak long enough for Morse to erase his memory with his own weapon.

Later, Fitz somewhat apologized to Simmons for not telling the truth, though, at the same time, he defended his choice, due to his belief that the others would have turned against Skye. The others, furious that he lied to them, essentially proved to him that his fears were correct, with Mackenzie stating they needed to be kept safe from Skye. She overheard the exchange, but would not stop to talk when Fitz chased after her; instead she retreated to the Bus.

Admiration
"You know, it could be just growing pains from your new powers." "That's alright, Fitz; you don't have to put a positive spin on this." "I'm not doing that. I would never patronize you."

- Leo Fitz and Skye

As Melinda May trained Skye, Fitz interrupted the session to check on her well-being. May became frustrated with his presence; so when he asked if it was worthwhile, May challenged Fitz to spar with her. Skye politely asked him to leave since she was doing well.

Jemma Simmons continued to give Fitz the silent treatment, telling Bobbi Morse that he violated the almost sacred respect they had for science by making false test results for Skye. She further explained that she was even more hurt that their relationship had deteriorated to the point where he lied to her.

When Andrew Garner arrived to give Skye a psychological assessment, Fitz learned that he was May's ex-husband.

Sometime later, Fitz wanted to microwave some food; when he went to the kitchen area of the Playground, he saw May laughing and smiling with Garner. He chose not to interrupt and traveled to where Simmons was working to heat his food. He told Simmons why he was there and how May was acting. This sparked a friendly conversation between them, speculating on Garner's and May's relationship.

Jemma Simmons checked Skye's casts; Fitz listened as Skye complained about how she internalized her power to show she had control. Fitz told Skye that he admired her for having a power, sparking an argument between Simmons and himself as they compared her to the Hulk and Captain America, respectively. The Bus started to shake; the two both apologized to Skye for arguing around and about her.

Fitz started spending a lot of time with Skye talking to her; so much so, Skye commented on it to Phil Coulson when he took her from active duty.

When he realized that Skye was gone, Fitz asked Simmons what she gave Coulson and how it was related to Skye. Simmons said that her efforts were for helping Skye's change. Fitz argued that Simmons was the one who had changed because she became closed-minded.

Feeling Betrayed Again
Fitz sarcastically asked Jemma Simmons how her science experiment was going after she communicated with Skye at the Retreat. Fitz was asked by Phil Coulson to determine what the extra mechanism was that Alphonso Mackenzie had within the toy replica of Lola that Coulson had kept in his office.

During the blackout caused from Bobbi Morse's EMP, Fitz was found by Melinda May. The two found Coulson and all compared notes; Morse stole the Toolbox and Mackenzie was on the run. Fitz told Coulson that Mackenzie had to be found as he went to secure the Playground.

Inside a maintenance closet, Fitz found a strange gadget. As he was investigating, he was approached by Mackenzie. Mackenzie told Fitz that he was not there to hurt him and would never do so, but he wanted Fitz to leave that closet. Fitz managed to grab a weapon to defend himself. However, he did not realize that Mackenzie was trying to protect Fitz from the gadget. Mackenzie quickly grabbed Fitz and fell upon him as the gadget exploded, allowing agents loyal to Robert Gonzales to enter.

As Gonzales agents stormed the base, Fitz and Simmons silently reconciled with each other, held hands, and tried to comfort one another when Anne Weaver approached Simmons to help to diagnose Mackenzie's wounds. Simmons did not comply until Fitz approved.

Non-Compliance
"There are no prisoners here, we are all S.H.I.E.L.D. Agents. Exit protocols have not changed." "Once you're cleared and debriefed you're free to go if that's what you really want." "Okay, I'll start packing my things."

- Robert Gonzales, Bobbi Morse and Leo Fitz

Robert Gonzales personally approached Fitz and Jemma Simmons as they stared at the Toolbox. He told them that he wanted them as his field agents, but Phil Coulson approached them first. Gonzales wanted Fitz to access the Toolbox. Simmons asked what would happen if he refused. Bobbi Morse explained that he could leave after he was evaluated and debriefed. Fitz told her that he was leaving to pack his belongings.

As he was packing, Alphonso Mackenzie approached him, calling Fitz by his nickname "Turbo." Fitz pointed out only his friend Mack would call him that, meaning that he no longer considered Mackenzie to be his friend since the betrayal. Mackenzie told Fitz that he would always be his friend and asked him not to leave, but Fitz continued to refuse. As they were talking, Mackenzie revealed that Simmons was working on accessing the Toolbox using Phil Coulson's DNA. Horrified that Simmons might have began working for Robert Gonzales, Fitz decided to investigate.

Fitz went to the Holocom and learned what Simmons was doing. He ran to Simmons' laboratory, asking why she was betraying Coulson and forcing him to leave. He grabbed the Toolbox and agents drew their weapons to have him release it. Fitz pitied them for their betrayal and their lack of trust in Coulson. Fitz then realized that Simmons wanted him to leave, and Simmons admitted that he felt that if they could not work together to unlock the Toolbox, it would probably best that he do so. He then left with Simmons giving him one of his bags.

Catching a taxi cab to the airport, Fitz looked inside his bag and pulled out the real Toolbox from the sandwich bag Jemma Simmons had given him, along with his favorite sandwich which he smelt with delight as he now knew that Simmons had not betrayed him and Coulson but was instead distracting Robert Gonzales with a fact Toolbox. However, he soon found out that Gonzales sent agents to track him under the hopes that he would lead them to Coulson. Fitz took the Toolbox to a diner, where he opened it in the diner's restroom, ignoring the knocks on the door from other customers. He accessed Phil Coulson's tablet from the box and contacted him and Lance Hunter, who were both shocked and surprised to see him. However, other patrons, who were in fact Robert Gonzales' agents in disguise, began to become impatient and continued to bang on the door. Fitz asked Hunter for advice on finding a way out, and Hunter began describing an escape method.

Seeing Ward Again
"Desperate times, desperate measures. Count me in." "I'm relieved to hear you say that, we're making a deal, with Ward"

- Leo Fitz and Phil Coulson

Fitz ran to the roof of a building and was picked up by Phil Coulson, Lance Hunter, and Michael Peterson, whom Fitz asked about his upgrades. He then gave Coulson the Toolbox and was briefed on their mission. Coulson explained that Skye had been taken by a teleporter and their only chance of finding her was to question HYDRA's current leader Baron Wolfgang von Strucker and Doctor List. When finding out that they would have to work with an enemy, Fitz agreed to it right away. However, upon hearing that they would be working with Grant Ward, Fitz was horrified.

Hunter pointed out that their jobs sometimes required them to work with people whom they despised, comparing the situation to his own frustration with working with Bobbi Morse again. When Coulson and Deathlok brought in Grant Ward and Agent 33, whom Ward had started dating, Fitz sat on an opposing side of the Quinjet, fingering his gun while Hunter tried to keep him calm. When Ward asked how Fitz was doing, Fitz lost his temper and leaped from his seat at him only to be held back by Coulson and Hunter. Once he had expressed his belief that Ward would betray them the first chance he got, Fitz calmed down, but still refused to answer Ward's question. When a brainwashed Sunil Bakshi set up a meeting with List, Fitz watched through Deathlok's eyes with the others. Bakshi offered up Deathlok as incentive, causing the Quinjet to erupt into violence, and Agent 33 held a knife to Fitz's throat. As the standoff continued, Fitz was the only one who noticed that Deathlok was targeting everyone in the HYDRA meeting. He told the others, and the standoff ended. Fitz told Deathlok to play along. Later, when the rest of the team followed List to a building in Milwaukee, Fitz stayed behind in the Quinjet as backup while everyone else entered the building. The mission failed, resulting in Skye and Calvin Zabo once again disappearing with the teleporter, during the battle Deathlok was captured by HYDRA and Lance Hunter was wounded. As a result Coulson turned himself into Robert Gonzales and the two worked out an arrangement to stop HYDRA. Coulson had Fitz, Hunter, Ward, and Agent 33 board the plane and fly back to the Playground. As they were doing so, Fitz talked briefly with Hunter, asking him about his wounds. Hunter replied that he was in more pain from seeing Ward and Agent 33 talking to each other like a couple.

Attack on the Arctic HYDRA Research Facility
After they returned to the Playground, Fitz and Jemma Simmons spoke about Grant Ward. Fitz told her about his attempt to kill him, and she seemed to be impressed. Simmons told him how she could kill him with a Splinter Bomb, but Fitz was worried about her because he realized she was serious. Phil Coulson decided to take Fitz, Melinda May, Simmons, and Ward on the mission to save Deathlok and Lincoln Campbell, who were imprisoned at List's base.

Preparing for the mission, Fitz and Simmons both expressed their mistrust toward Ward. Fitz expressed his wish to kill Ward, and Simmons suggested that they could, revealing that she planned to kill Ward with a Splinter Bomb.

As they got on the plane, Gordon teleported Skye onto it, reuniting her with her old team, much to Fitz and Simmons' pleasure. Fitz and Simmons eagerly asked her lots of questions about where she had been and about her powers, but Skye was reluctant to answer them with Ward around, but she promised that she would tell them everything soon.

Ward prepared to update the team about their mission; Fitz stood and watched him. Ward sensed the team's hostility towards him, so he tried to apologize for betraying the team, admitting that that was what he regretted most, not even ejecting Fitz and Simmons' pod into the ocean. He tried to remind the team of the good times that they had, but everyone, including Fitz, remained unmoved by what he said and expressed their anger towards him.

After the team sacrificed the Bus to get into List's base, Fitz went with Coulson and May to break into the missiles system and gather information about HYDRA, while Simmons went with Skye, Ward, and Sunil Bakshi to save Deathlok and Campbell. After Fitz succeed in his mission and abducted were saved, the team returned to the Playground and the base was destroyed. He and Simmons talked with Deathlok and said to him that there was facility which had the equipment to repair his dismantled leg.

At the Playground
"What if the council is wrong? I mean, Gonzales is never..." "It's not the council verses us, Fitz. Not anymore."

- Leo Fitz and Phil Coulson

Fitz and Jemma Simmons looked at Skye, as she sat near the anesthetized Lincoln Campbell. Then, they informed Kara Palamas that the brainwashing of HYDRA was not affecting her reactions anymore. Palamas thanked them but then the light of the building turned on and off, as Campbell awoke from his coma. After S.H.I.E.L.D. located the Inhumans' base, Afterlife, Fitz and Simmons were with Skye and said their goodbyes before she returned to the base as a part of S.H.I.E.L.D.'s plan reaching an agreement with the Inhumans with their leader, Jiaying, who was also Skye's mother, and putting them in the Index. Before Simmons went to Afterlife as the agent-in-charge of the Index process, Fitz talked with her and admitted that he had wanted to kill Grant Ward but was unable to do it and was glad that he did not become a murderer. He was also glad that Simmons did not kill Ward either, but Simmons admitted that she had indeed tried to kill him.

Fitz was in Coulson's office along with Coulson and Lance Hunter while S.H.I.E.L.D. was on the way to meet the Inhumans. Hunter doubted Coulson's decision of sending Robert Gonzales to meet Jiaying and not him. Even Fitz questioned the council's decision, but Coulson said to him that it was not the council versus them anymore and they were right about their decision. He said that he had not always made the right call, especially where it had came to Skye, and if they did not trust the council, S.H.I.E.L.D. would fall again. Hunter joked that S.H.I.E.L.D. would fall again if a dozen enhanced people will bring terror on them, to which Fitz agreed. Coulson then said that he thought that they had spent too much time together. Just then, Melinda May informed them that the Inhumans turned over Calvin Zabo, to which Coulson said that they will deal with this when they had returned to the base.

Finding Bobbi Morse
"Figured out what happened to Agent Morse. She left on a Quinjet with... you."

- Leo Fitz

After a while, Melinda May talked with Phil Coulson, saying that Bobbi Morse had not arrived at Afterlife yet. Coulson sent Lance Hunter to check what had happened to her. Suddenly Jemma Simmons joined the conversation and said that Robert Gonzales had allegedly shot Jiaying. Fitz said that he had got what he always wanted, but Coulson said that Gonzales had not done this and ordered them to find him.

Fitz then joined Hunter in the search for Morse. He checked the flight records from the base and saw that Morse had left the base with a Quinjet before the three others left for Afterlife. Hunter told him to change access and check the security cameras to the time before she left the the base. Fitz discovered that May had left the base twice; one time with Morse and the other time with the delegation of S.H.I.E.L.D. to Afterlife. Hunter realized that it was Agent 33 who was disguised as May and took Morse on a Quinjet. Fitz asked Hunter what Agent 33 wanted with Morse. Shocked by their discovery, they went to Coulson's office and showed the footage to Coulson, Melinda May and Jemma Simmons. Hunter said they found where the Quinjet was and May volunteered to take him there.

Calvin Zabo's Transformation
"Fitz, I'm open to suggestions." "I.C.E.R.s are a good start." "Agreed."

- Leo Fitz and Phil Coulson discuss defusing Calvin Zabo

Calvin Zabo was brought to the Playground and interrogated by Phil Coulson; Zabo soon afterwards had a heart attack. He was brought to the lab where Jemma Simmons tried to revive him. Failing, she asked Fitz for an adrenaline syringe. She injected him, but it caused Zabo to transform into a powerful monster. In the moment Zabo was locked up in the medical pod, trying to get out, Coulson asked Fitz for suggestions and Fitz said that I.C.E.R.s could be a good start. As Zabo escaped from the pod, Fitz, Coulson and Simmons started shooting at him with the I.C.E.R.s, but they had no effect on him. Coulson ordered Fitz and Simmons to get out of there. Shortly after, when Zabo walked around the base, Fitz and Simmons lured him into the hangar where Coulson could reason with him.

Preparing for a Counter Strike
"Sir, good news. I've modified my field generators to act in unison as a quantum-field disrupter." "Great, you're saying you found a way to shut down Gordon's teleportation ability?" "Well, now my news sounds less good." "Oh, sorry."

- Leo Fitz and Phil Coulson

Phil Coulson convinced Calvin Zabo to assist them against Jiaying, and Zabo was put under armed guard while Jemma Simmons helped counteract the effects of his formula, resulting in the reverse of his physical changes. Fitz then informed Coulson that a distress beacon from the Iliad was expanded to all of S.H.I.E.L.D. channels. Coulson realized that the Inhumans had hijacked the ship while they were fighting Zabo. Coulson asked Fitz if he got Lance Hunter and Melinda May on the line, but he responded that he could not communicate with them. Fitz then came to Coulson's office to inform him that he had built Quantum Field Disruptors that could make Gordon stay in a single location. Fitz and Coulson visited the room where Bobbi Morse would be analyzed since she had been badly injured. Coulson asked Simmons if Zabo was stable enough to join them in their mission to retake the Iliad, but Fitz and Simmons were surprised to hear that.

While preparing himself for going with Phil Coulson, Melinda May, and Calvin Zabo to retake the Iliad, Fitz was visited by Jemma Simmons. She started to explain that after she saw Lance Hunter with Bobbi Morse, she realized that they had never spoken about what Fitz had said her in the bottom of the ocean. Fitz was surprised to hear that. He said to her that there was nothing to be said about about it, but Simmons said that maybe there was. Coulson then came and informed Fitz that there were on the move, so Fitz followed him, leaving Simmons standing alone and crying to herself.

Hijacking and Retaking of the Iliad
"I'm trapped in here! That's not possible! What did you do?!" "Science, biatch."

- Gordon and Leo Fitz

In one of the Quinjets heading to the Iliad, Fitz informed Coulson that someone had changed the S.O.S. signal. Coulson realized that it was Skye who had done that and Fitz said that she warned them that they were flying to a trap. Coulson ordered the other Quinjets to fall back while they still flew to the ship. As they landed on the the ship, Fitz got another message from Skye, which warned them about synthetic Terrigen Crystals in the HVAC room. Zabo then understood Jiaying's plan: she wanted to use the Terrigen Mist in the crystals to kill all the S.H.I.E.L.D. agents. Coulson and Fitz went to find the Crystals, while Zabo went to find Jiaying and May went to the HVAC room. The two eventually found Alphonso Mackenzie protecting a box full of Crystals from Gordon. Fitz started to put the Quantum Field Disruptors in their places. As Gordon returned, Fitz activated the devices and they succeeded in preventing Gordon from teleporting to a different location. The three continued fighting Gordon, but he managed to take one Crystal. He then teleported himself directly behind Fitz, but he was impaled by Fitz's iron pole while he was holding it. Gordon then dropped the Crystal, but Coulson caught it. Then his arm started to petrify, but Mackenzie used his axe to cut off Coulson's hand.

New Programs
"I got Fitz working on these designs. We'll need to be mobile."

- Phil Coulson

With the threat quelled, Phil Coulson asked Fitz to work on a new plane for his new program he founded. Fitz also helped Alphonso Mackenzie, who was now the head of the Alien Artifacts Department, to work on the Monolith on the Iliad. Although Jemma Simmons continued to push the idea of examining the Monolith, Mackenzie insisted that they must not open the box in a thousand years as it was too dangerous.

As Fitz and Jemma Simmons worked on the stone, Fitz awkwardly tried to ask Simmons to go to dinner with him, although Simmons at first believed he was asking her to eat generally, she soon realized what he meant and agreed to have a date with him. Fitz leaned on the Monolith's casing and stumbled, causing the lock on the case to loosen. With Simmons having finally agreed, Fitz left the room. Without knowing it however, he had caused the stone's casing to unlock allowing the Monolith to swallow her. Simmons then disappeared without a trace.

Seeking Answers
"I'll open it and give you what's inside, no problem. But only in exchange for something in your possession." "How about in exchange for your life?" "No deal."

- Leo Fitz and Yusef Hadad

Not willing to give up hope on finding Jemma Simmons again, Fitz dedicated his time and work to studying the Monolith in the hopes of finding an answer. This led him to questioning if she had been sent to a parallel dimension or lost to the Quantum Realm like Janet van Dyne. The more questions he asked, the more time he took off from S.H.I.E.L.D.. Eventually he learned of a scroll casing which was said to hold the answer to the Monolith's power; Fitz tracked the scroll to the criminal Yusef Hadad, who had stolen it. Fitz tracked Hadad to Morocco and offered him the contents of his briefcase; Hadad's men captured Fitz and only spoke to him when they discovered the briefcase could not be opened without the password. Fitz explained his reasons for coming and told Hadad that he would only open the case if Hadad gave him the scroll casing. Hadad acquiesced and handed over the casing, ordering Fitz to open the briefcase; Fitz did and handed over the Splinter Bombs inside, explaining that they were the weapons that killed Sunil Bakshi. When Hadad tried to kill Fitz with the bomb, it activated the flash grenade inside. During the ensuing chaos, Fitz escaped with the scroll casing while Hadad's men shot at him.

Never Giving Up
"Do something... Do something!... DO SOMETHING!... DO SOMETHING!"

- Leo Fitz to the Monolith

Back at the Playground, Fitz found Phil Coulson waiting for him. Coulson tried to sympathize with Fitz's feelings by comparing his loss of Melinda May to Fitz losing Jemma Simmons; Coulson attempted to convince him to move on but Fitz remained determined. He smashed open the casing and read the scroll, translating the word to "Death". Seeming to accept this as the final confirmation that Simmons had been killed by the Monolith, Coulson comforted Fitz and told him it was time to finally move on and continue with their work. Unable to accept that Jemma Simmons was dead, Fitz, after Coulson left, grabbed a shotgun and charged into the room containing the Monolith, ignoring the warning signs and kicking open the door. Without hesitation or fear, Fitz shot the locks of the Monolith's casing and stepped into its protective box. Fitz at first quietly spoke to the stone, asking it to do something and give him an answer; when nothing happened, he began to lose his temper before screaming at the stone and demanding it to do something, all while punching and kicking it to make it respond. Despite his screams, tears and strikes, the Monolith remained a stone and did not give him the answers he sought. Lance Hunter and Bobbi Morse then charged into the room followed by Phil Coulson, Alphonso Mackenzie and Daisy Johnson. They pulled Fitz away from the Monolith and locked its case seconds before it transformed into its liquid state again. Coulson berated Fitz over being so foolish, noting that he had already lost Jemma Simmons to it and could not afford to lose him too. Fitz apologized but assured him that he would never give up on finding his friend. As he sat on the ground, Fitz noticed a strange sand on his fingers which he had gained from touching the Monolith; seeing the sand gave Fitz an idea and he ran from the room. Once he had confirmed his theory, Fitz called the team into Phil Coulson's office where he pitched them the idea that the sand was impossible and should not exist; therefore, it must confirm that the Monolith is a transportation device and had sent Jemma Simmons to another point across the universe. Coulson tried to make Fitz accept that it was possible that although he could be correct, Simmons may well be dead anyway having been lost for months; this did not stop Fitz and they agreed to continue researching his theory. While Fitz confirmed what he needed, Coulson sent Lance Hunter on his mission to hunt down and assassinate Grant Ward.

Help from an Asgardian
"You'll have to go through me." "And I could. Literally."

- Leo Fitz and Elliot Randolph

Fitz joined Phil Coulson and Bobbi Morse in traveling to Norway to seek the help of the Asgardian professor Elliot Randolph, who had been arrested for getting drunk and damaging property. Although Randolph initially made it clear that he had no wish to help as he was trying to keep his Asgardian powers quiet due to the recent fears of the public, Fitz made it clear they did not have time to wait and Coulson was able to change his mind with a threat of handing him over to the ATCU. Randolph reluctantly agreed and ripped the bars off his cell and left with them. Returning to the Playground, Randolph looked at the Monolith and was fascinated, having never seen such an artifact before. As they discussed its powers, Randolph made it clear that they should destroy it; Fitz assured him that he would have to go through him first. Not wishing to kill Fitz, Randolph relented and asked for more information. The team told him about the scroll which Fitz had recently recovered and Randolph recognized the writing from a castle he had visited hundreds of years ago. Confirming his thoughts, Randolph told everyone to join him in the plane to investigate.

Further Experiments
The team traveled to England to the castle which Elliot Randolph had visited all those years earlier. Randolph confirmed that it was the same castle and described the party he had attended there where he had seen the writing on the walls of the castle. The group found the writing and before long, Phil Coulson found a secret passage leading to another room which Randolph had never seen before. The room was filled with ancient machinery and a trap door which seemed like the perfect size to hold the Monolith. Once they confirmed the room was designed to test the Monolith's power, Coulson called Alphonso Mackenzie and ordered him to bring it to them. Although reluctant, Mackenzie brought the Monolith to them in Zephyr One and they set it up for their experiment. Fitz led the team in setting up their equipment as they worked out how to work the machinery. They turned on the machine which triggered a vibration that caused the Monolith to transform into liquid; Fitz looked down at it and called out to Jemma Simmons. Demanding more light to see, Phil Coulson threw Fitz a flare gun which he fired into the liquid, making it instantly vanish. Before they could get their answers however, the machine broke and the Monolith returned to stone. The vibrations also caused Daisy Johnson to collapse as she complained of a terrible noise which nearly killed her.

Saving Simmons
"And you dove through a hole in the universe for me."

- Jemma Simmons

Despite the machinery being broken, Fitz worked out that Daisy Johnson could use her powers to trigger the same effect. Johnson agreed despite the terrible effect it would have on her and the experiment was set up for a second attempt. Johnson used her powers to create a small earthquake which caused the Monolith to turn to liquid; while Coulson and Bobbi Morse set up a video feed to drop inside, Fitz attached a rope to himself and jumped inside. Fitz fell onto a desert planet in the middle of a sandstorm. Without hesitation, he began to desperately call out for Jemma Simmons. To his shock, Simmons answered him and he saw her appear from behind a rock. The two friends called out to one another and desperately fought against the powerful winds to reach one another. However, back on Earth, Johnson struggled to control her powers and to keep the Monolith liquid, forcing Phil Coulson to order that Fitz be pulled back. Fitz was just able to grab Simmons' hand as he was pulled back into the portal. The moment the pair were sucked back to Earth, Johnson collapsed and the Monolith exploded. Fitz hugged his friend and smiled to the team as they celebrated their victory. Once she had gone through medical tests and deemed to be safe from infection and physically well, Simmons was allowed to go to sleep aboard Zephyr One. Fitz stayed by her bedside while she slept. Once he had fallen asleep, Simmons awoke from a nightmare and attempted to defend herself with a blade. However, once she remembered where she was, she turned to see the sleeping Fitz sitting beside her. Simmons found comfort resting on Fitz's lap and fell into a more peaceful sleep.

Caring for Simmons
Fitz and the team discussed the physical changes Jemma Simmons had experienced in the other world. He then helped her adjust to the Earth gravity and accompanied her to the lab, where Bobbi Morse welcomed her. She then saw the remains of the Monolith. Fitz noticed that small noises diverted her attention and Simmons told him that she wanted to go to her room to relax.

He then spoke with Morse about how distanced Simmons was. Morse told him that Simmons needed a fresh start to learn how to live again on Earth. Fitz then left the room and reserved a place in a restaurant for him and Simmons.

He brought Simmons to the restaurant and told her that the reservation had been waiting for months and he planned it so that they would eat alone. Simmons said she did not know what to say for what he had done for her, so Fitz said that she did not have to say anything. But as she started to cry, Fitz sat next to her and comforted her.

Supportive Friend
Fitz was sent with Bobbi Morse to Hollywood, California to gather evidence from the apartment of Shane and Lori Henson, two Inhumans killed by Lash. Fitz became annoyed with Morse because she had difficulty adhering to the system that he and Jemma Simmons had developed. He asked Morse if Simmons revealed anything to her about her experiences on the other planet; Morse lied, saying that she knew nothing. Returning to the Playground to analyze the samples, Morse alerted Fitz when the hair sample of Lash began to dissolve. While discussing the strange occurrence, and if Morse had somehow contaminated the sample, Fitz found a notebook filled with research on the Monolith. Simmons ran into the lab and abruptly grabbed the notebook from Fitz, causing the paper to fall to the floor. Collecting her research, Simmons told Fitz to leave her things alone as she left.

Later, Fitz went to Simmons' room and asked her why she was researching the Monolith; Simmons decided to give him full disclosure about her experience on the other world. After telling him about her ordeal and her relationship with Will Daniels when she gave up hope of being rescued, Fitz left the room without speaking to Simmons. She, teary-eyed, begged him to understand her feelings. Fitz told her that he did understand her feelings and showed her his computer screen; it revealed the research that he had done over the past six months that she had been absent to locate her. Fitz declared that they would save Daniels and return him to Earth.

Research
"What? You don't think I should help Simmons rescue Will?" "Do you think you should? He's the competition."

- Leo Fitz and Lance Hunter

Fitz was assigned to act as technical support for Melinda May and Bobbi Morse as they went to the Cayman Islands in search of Werner von Strucker, so he allowed his computers to run simulations pertaining to the Monolith as he made cover aliases and backgrounds. Lance Hunter, having been reassigned for his actions in the Attack on Grant Ward, entered Fitz's workplace, seeking something to do. Hunter asked Fitz why he was helping Jemma Simmons to rescue Will Daniels, a man about whom he knew nothing, when Fitz had feelings for Simmons; Fitz did not answer, asking Hunter why he was there. Hunter wanted to help him, but Fitz quickly asked him to leave when he began touching the computers.

During their undercover mission, Morse needed background information on Jerome Deschamps in an attempt to diffuse a situation; Fitz did the research and conveyed the information to the sunglasses Morse wore.

Evaluating the fake IDs and passports found in Strucker's lock box, Fitz determined that Strucker was in Lisbon, Portugal and told Morse and May. Meanwhile, Simmons was behind him, finishing her technical support for Daisy Johnson; she then asked Fitz how his research into the Monolith was progressing. He said that the simulations had not yet found a solution. After Simmons left, Fitz returned to reading background information and newspaper articles on Daniels.

Accessing Simmons' Phone
Jemma Simmons asked Fitz to fix her phone that she had used during her survival on Maveth; Fitz uncovered some of her files, which included a video of Simmons' birthday party in 2014. Fitz watched in awe and shock as he witnessed her submitted logs and images about the groundbreaking realities of the planet and that of Will Daniels.

After he had given the fixed phone to Simmons, Fitz questioned her about her entries, wondering about her state of mind as she placed them; Simmons, knowing that he was referring to her affirmations of love and wanting a family with him, assured him that she had full clarity when she made her statements. He then too watched the sun rise. Continuing his research, Fitz noted to Bobbi Morse and Lance Hunter that Daniels had a symbol on his uniform similar to one he had seen in the English castle, weeks ago. Morse thought that NASA had sent Daniels through the Monolith, but Fitz gave a theory believing that an ancient order truly sent Daniels; Hunter dismissed Fitz's conspiracy theory as lunacy.

HYDRA's Revelation
Continuing research into his theory, Fitz had scrolls and books brought to the lab. The agent moving the books dropped them, and Fitz angrily confronted him over his carelessness. Jemma Simmons calmed him down, before becoming angry with him when he mentioned bringing back Will Daniels. She returned to the lab, and Fitz followed her, asking her why she was angry at him. Simmons replied that she was angry with herself for bringing him into her search along with being angry with him for being so willing to bring back Daniels. Fitz retaliated, saying he was incredibly angry and sick, not at Simmons but at the cosmos, for keeping them apart.

Though Simmons disagreed, Fitz listed all the obstacles to their relationship, culminating with Daniels. Fitz asked Simmons if she loved Daniels, to which Simmons hesitatingly answered yes. Fitz agreed and began listing all of Daniels' character traits, saying that he had done everything for Simmons. However, Simmons cut him off and reminded Fitz that he had jumped through a portal to rescue her. Fitz stared at Simmons for a second, then kissed her. Simmons kissed him back, but Fitz broke away and mouthed 'I love you' to Simmons before whispering that they were cursed and walked away.

He was called back by Simmons when she noticed that a book that had fallen off the desk had opened to a page with a symbol similar to the modern HYDRA insignia. The two realized that HYDRA was behind Distant Star Pathfinder and had been sending people through the portal for centuries. Fitz and Simmons revealed their research to the other agents, laying out paper with each insignia, beginning with the Distant Star Pathfinder logo and continuing to the HYDRA symbol. Their research showed that HYDRA was inside NASA and the Advanced Threat Containment Unit.

Kidnapped
When Rosalind Price was killed by Grant Ward, Phil Coulson sent Fitz, Jemma Simmons Luther Banks, and a team of agents to an abandoned Project Distant Star Pathfinder facility in search of clues to the Monolith. While there, Simmons expressed her belief that it was unlikely they would find anything, but Fitz replied that they still could find something to help them bring back Will Daniels. Simmons told him that they could not bring him back, but Fitz said that they now knew exactly where the portal would open on Maveth, so they had to go there. Simmons told him that it would be selfish to potentially allow HYDRA to achieve their goal, but Fitz said that the HYDRA leader was only a legend. Suddenly, the two heard shots. Quickly turning, Fitz saw Banks shoot the other agents, then turn the gun on the two. Fitz asked Banks not to shoot them; however, Banks managed to say it was not him before the gun floated out of his hand, turned, and shot Banks in the head. Fitz and Simmons watched as Giyera entered the room and ordered them to follow him.

In the HYDRA Castle, Fitz and Simmons were brought to Ward and Gideon Malick. Fitz refused to help them open the portal, but Malick claimed that they did not need their help, so Simmons understood that they did not know how to bring someone back from there. Fitz Simmons refused to cooperate with them, so Ward ordered to separate between the two. Fitz was tied up to a chair and heard Simmons' cries from the other room, and Ward told him that he could end this by telling them what they need.

Entering Maveth
"I lost you once. I can't lose you again. I'm just I'm not strong enough to live in a world that doesn't have you in it."

- Leo Fitz to Jemma Simmons

Unable to stand hearing Jemma Simmons being tortured, Fitz agreed to enter the portal and guide HYDRA's team. Entering the portal chamber, Fitz saw Simmons restrained by Giyera. She broke free from his hold and ran to Fitz; when Giyera started after her, Fitz told him that the deal was off if he touched her. Simmons begged him not to go, but Fitz assured her that the only thing he would bring back would be Will Daniels. Hugging Simmons, Fitz saw Grant Ward enter the chamber in full combat gear. Asking him what he was doing, Fitz learned that Ward was leading the HYDRA team. The portal opened and Fitz, Ward, and the other agents jumped through. Once through the portal, the team began searching for It. Hiking up a rise, Fitz tried to distract Ward by showing him the program he was using to find the exit portal, before going for Ward's gun. However, Ward realized his intent and kicked Fitz down a ridge before following him down and threatening that Simmons would die if he did not return, and it would be Fitz's fault. One of Ward's soldiers called out for him to come and he walked away. Fitz followed him to the soldier, where he saw an old structure in the shape of HYDRA's symbol. Fitz continued on with the team. Fitz realized that the area that they were walking through was familiar; looking around, he noticed a metal hatch in the ground. Knowing he had found the home of Will Daniels, Fitz entered the hatch, with a furious Ward following him. Once in the cave, Fitz found what he believed to be Daniels with an injured leg on his bed. "Daniels" sat up and questioningly recognized him; Fitz confirmed that it was him as Ward stormed in, angry that Fitz had entered the cave without permission. Fitz panicked as Ward threatened to shoot "Daniels", hastily explaining that "Daniels" was to be their guide and he was the only way to find It. Ward noticed the insignia on "Daniels"' suit and agreed to take him, first offering Fitz the chance to shoot him. Fitz told Ward to grow up and once he had confirmed that "Daniels" could walk, the group left the cave. Walking with "Daniels", Fitz explained that Ward was part of an organization dedicated to bringing back their leader, It. Fitz listened as "Daniels" informed him that they were in the 'no fly zone'. Fitz listened as Ward asked "Daniels" what the structure they had seen was; "Daniels" told him that it was a shrine to It, and that It had lived there. "Daniels" formed a plan to escape from Ward and ordered Fitz to follow his lead. As they continued, a sandstorm began to form, and the team eventually had to shelter behind some rocks. Fitz watched as "Daniels" killed the two HYDRA agents sheltering with them, and he and "Daniels" crept away before Ward realized their escape. Fitz and "Daniels" continued on towards the exit point. As they walked, Fitz saw an ancient city, and asked "Daniels" about it, asking why Simmons had not told him about it. "Daniels" replied that she had never seen it, and explained that there were nine such cities, and the inhabitants had torn each other apart. Suddenly, "Daniels"' leg gave out and he fell. Fitz ran to him and pulled the bandage away to try to assess the damage; he saw only bone and rotting flesh, and realized that what he had believed was Will Daniels was in reality It, inhabiting Daniels' corpse. It began attacking Fitz, who held It off for a time, but was beaten back. Just as It was about to crush Fitz with a rock, It was shot by Phil Coulson. Fitz got up and watched Coulson fight Ward, before realizing that It had also regained its feet and had begun walking towards the now-opened portal. Fitz found a gun and shot It again, but It continued on. Finally, Fitz discovered his flare gun and engulfed It in flames, finally stopping the dark Inhuman. Realizing that the portal was about to close, Fitz screamed for Coulson. Fitz watched Coulson kill Ward, before both entered the portal and were rescued by Alphonso Mackenzie, back on Earth as they made their hurried escape. Getting onboard the Containment Module, Fitz, Coulson, Mackenzie and Daisy Johnson managed to escape the HYDRA Castle just as it was destroyed by missiles. Reaching Zephyr One the group reunited with their friends and teammates while Fitz watched as Simmons searched for Daniels inside the empty Containment Module, before realizing he was not there and turning back to Fitz as she began to cry. Fitz hugged Simmons to comfort her over the loss of her friend and lover, and shared a look with Coulson, knowing that Coulson had killed Ward in cold blood.

Missed By Simmons
"I miss you." "I'm here." "Together. We're professional and matter of fact, and there's this chasm in the middle of the room of all these things."

- Jemma Simmons and Leo Fitz

While he was in the lab, assisting Jemma Simmons, Phil Coulson asked Fitz to come with him. He asked Fitz's opinion on Lincoln Campbell, so Fitz replied that Campbell had helped Simmons understand the Inhumans' biology. Fitz also told Coulson that he felt guilty for what he had done to Will Daniels. Coulson explained that he had made the hard choice. Coulson then ordered Fitz to set up the Theta Brain-Wave Frequency Machine. At first, Fitz refused, but Coulson said that it was for Werner von Strucker, who might know where Gideon Malick was. Coulson eventually got the information. Later, Fitz finished working on Coulson's new robotic hand, as Simmons entered the lab and said that she missed him. Fitz was confused, but Simmons explained that she missed their partnership because of the recent events. Fitz told her that maybe there had been a way to save Daniels, but Simmons said that he was extraordinary, since he had killed Hive. Together they restored the moment they had met, reintroducing themselves in an attempt to start over.

Potential Cure
"Creel's blood is protecting hers." "A vaccine against Terrigenesis." "Potentially."

- Leo Fitz, Lincoln Campbell and Jemma Simmons

Fitz made a device for Phil Coulson that could replicate people's fingerprints. As he brought it to Zephyr One, he spoke with Lance Hunter about the Inhumans symposium. Later, Carl Creel was brought to the Playground and put inside a Containment Module. Fitz and Jemma Simmons asked him how he had touched the Diviner without being killed, but he did not know. They decided to test his blood samples with Terrigenesis. The two showed Lincoln Campbell that Daisy Johnson's pre-Terrigenesis blood reacted to the Terrigen, but as they mixed it with Creel's blood, it broke down the Terrigenesis. They theorized that it could be a vaccine to Inhumans that were not yet transformed. Johnson entered the lab, shocked at the idea. Fitz and Simmons left the room to let her and Campbell talk.

Losing Friends
Bobbi Morse and Lance Hunter followed Gideon Malick to Siberia and the rest of the team followed them. Fitz, on Zephyr One, helped the pair to go to a massive compound in the wood. Morse and Hunter were caught after they entered the building. Phil Coulson asked Fitz to activate an EMP in Morse and Hunter's investigation room by his signal, but no signal was made. Coulson returned from where they had been interrogated, saying that in order to keep S.H.I.E.L.D. a secret, the two had been disavowed from the agency. Later, the team went to a bar where Morse and Hunter were. Without directly contacting them, Coulson and the others all ordered shots for the two, saying goodbye in the only way they could.

Almost Imploded
Following the Attack on the ATCU Headquarters by the Watchdogs, Phil Coulson sent Fitz Daisy Johnson the the scene. Fitz discovered that the Watchdogs had use Nitramene to collapse the building. Johnson sent the information to Coulson, who suspected Felix Blake had to do with the incident. Fitz heard Johnson and Alphonso Mackenzie weather they should let her using her powers to interrogate members of the Watchdogs. Ftz then helped Johnson interrogating a Watchdog member by pointing a gun at him, despite his unwillingness. After he told them the location of the Watchdogs base, they went there. Fitz sent a D.W.A.R.F. to a barn where they saw Blake. However, one of the Watchdogs shot a Niteramene at Fitz's neck. Johnson could not defect it, so Fitz realized Blake had improved it. In a Containment Module, Fitz learned from the member how to defect it. After Johnson saved him, the member told them the Watchdogs were after Mackenzie.

Spacetime Theory
"Was that Ward?" "Unfortunately, I think it was something else."

- Lincoln Campbell and Leo Fitz

Daisy Johnson saw a vision of the future from the Inhuman Charles Hinton. After she returned to the Playground, Johnson told the team she would fight HYDRA to rescue Hinton from them and Fitz and Jemma Simmons would hold hands as the snow falls. Johnson said they could change the future from happening, but Fitz explained to the team that time was an illusion of the fourth dimension, therefore the future could not be changed. Phil Coulson suggested they would send Melinda May to the mission.

Johnson gave details of the location of the battle to Fitz and Simmons, and they used S.H.I.E.L.D. services to find it. May entered the room and demeaned they would not use all of them. Simmons explained that she and May used some of the services to find Lash. Fitz joined Simmons, Lincoln Campbell and others as they began training to ensure Melinda May would undergo her mission as fast as possible in order to change the vision's outcome. Despite Fitz's doubts, Johnson made sure the room was laid out as accurately as possible to the vision she had had while Fitz and the other agents acted as the guards who needed to be taken out. Eventually May managed to beat the time limit.

They eventually found the location of the battle, which was owned by Transia Corporation. Coulson said he had heard of them so Fitz said he had used their technology for his prosthetic hand. Coulson gave his last orders to May when suddenly the alarms in the base went off, telling them that there was an intruder. Andrew Garner was brought into the base and explained that Lash was taking over and he wanted to say goodbye to May.

May was ordered to stay behind so she could say goodbye to her ex-husband while Johnson went into the mission and Fitz managed to hack into Transia Corporation's CCTV feed. In Coulson's office they watched as they managed to hack into the Transia Corporation's CCTV feed. As they spotted Giyera on the feed, suddenly the video seemed to show Grant Ward in the building. Fitz claimed it was likely to be Hive. They went to the building to save Johnson and find Ward. Fitz and Simmons stayed outside. Seeing no cloud in the sky, Fitz said that maybe Johnson had not seen the future. Suddenly, Fluorescent sparkles fell from the building's rooftop, so Fitz realized Johnson had not seen snow. Simmons said they supposed to hold hands now, so the two did it.

Studying Hive
"You were left no choice on that planet. You did the right thing, but I crossed the line. Ward deserved to be punished, but no one deserves to have the life s..." "No, he did deserve it. He did deserve to have his chest caved in no question."

- Phil Coulson and Leo Fitz

Fitz, Jemma Simmons, Daisy Johnson and Alphonso Mackenzie examined skeletons sentenced from the skin by Hive. Fitz explained that Grant Ward's body was possessed by the Inhuman from Maveth. The team was called to Phil Coulson's office for a meeting where he explained that in order to find Hive, they would go to GT Agrochemical facility which had been raided by HYDRA. On Zephyr One, Fitz and Simmons explained to Coulson that Hive had created small organisms which had consumed the victims' flesh. As the team prepared to enter to facility and to face Giyera there, Fitz explained them his powers. Melinda May asked him about a room in the facility where she could defeat him. After they kidnapped Giyera, Fitz found that the data of the facility had been moved to an oil field in Schoonebeek. Fitz found a frustrated Coulson. He asked him if he was fine, so Coulson explained that in contrast to the justified act against Hive Fitz had done on Maveth, he should not had kill Ward. Fitz tried to conform him by saying Ward had to die, but Coulson said that now he Ward was basically after him. Fitz then was near to the Containment Module where Giyera was inside it. Suddenly he noticed that one of the seat belt was missing a buckle. Giyera used it to escaped the module and Fitz set the alarm. He pointed a rifle at Giyera but the latter managed to take it. Fitz revealed it had no bullet so Giyera threw it towards Fitz but he missed. Mackenzie tried to beat Giyera but he failed and Giyera managed to bring the plane to the oil field.

Battle at Gideon Malick's Headquarters
Fitz, Jemma Simmons, Phil Coulson and Alphonso Mackenzie helped a wounded Melinda May to get shelter in a storage room at Gideon Malick's Headquarters. The room was soon assaulted by HYDRA agents who began to ram the door. While Simmons took care of May's wound, Fitz and Mackenzie spread chlorine gas in the corridor, making the HYDRA agents cough and blinding them. The group was then rescued by Elena Rodriguez and Daisy Johnson before returning on the Zephyr One.

Back at the Playground, Fitz and Simmons noticed that the dead body of Lucio, killed by Joey Gutierrez during the battle at Gideon Malick's Headquarters, maintained a high body temperature, and thus placed the corpse in quarantine. Fitz later assisted Simmons during Lucio's autopsy, looking for a way to determine whether one of the S.H.I.E.L.D. Inhumans was infected by Hive. Fitz displayed some discomfort, both because of the autopsy and because of the fact that they could not trust the Inhumans present at the Playground. The two scientists then discovered the signs of Hive infection in Lucio's brain, and reported their discovery to Coulson.

Immediately after that, the power was cut at the Playground. Fitz and Simmons made their way to the generators room and, on their way, discovered the dead body of Gideon Malick with a grenade beside it. The grenade exploded, throwing Fitz and Simmons on the ground. They were found by Coulson who ordered them to get some rest in a calm place, with Fitz abruptly rebuking Lincoln Campbell when he offered his help since they still did not know whether he was infected by Hive or not.

Fitz and Simmons went to Fitz's bedroom where they kept searching for a test for Hive's infection. Both sitting on Fitz's couch, they contemplated one of his pictures of cosmos, discussing Hive, and Fitz jokingly noted that Hive was unable to leave Maveth without the help of humans. Fitz and Simmons then shared a tender look, holding hands before slowly kissing. Fitz apologized, remembering that Simmons had proposed to start their relationship from the beginning. However, Simmons replied that they had known each other for 10 years and that, since Fitz considered that they were "cursed", they couldn't waste any more time. They kissed again and stayed in Fitz's bedroom until Daisy Johnson, who turned out to be infected by Hive, escaped from containment by generating a earthquake which damaged the Playground.

Meeting Holden Radcliffe
Fitz ensured the rebooting of the system with the help of Lincoln Campbell. He later attended the crisis meeting held by Phil Coulson before leaving the Playground with the Zephyr One, along with the rest of his friends. He and Jemma Simmons then informed Coulson that Hive's infection on the Inhumans had the same effect than a drug addiction, making them invulnerable to I.C.E.R. shots. They suggested to make contact with Pr. Holden Radcliffe, a scientist specialized in parasitic organisms who used to work at GT Agrochemical. Radcliffe was fired from the company due to the transhumanist experiments he conducted.

Coulson sent Fitz, Simmons and Alphonso Mackenzie to Romania in order to retrieve Radcliffe. While preparing for the mission, Fitz and Simmons, acting as they were having a professional conversation due to the presence of numerous S.H.I.E.L.D. agents around them, discussed the future of their relationship after the kiss they shared the day before, especially in the perspective of having sex. However, they were interrupted by Melinda May.

In Bucharest, Fitz, Simmons and Mackenzie rented a hotel room and prepared for their mission in a private club where Radcliffe was supposed to be. Fitz and Simmons posed as two high ranking geneticists willing to sell an advanced technology to Radcliffe : a variation of the eye technology implanted in Deathlok. Mackenzie stayed in the hotel room, following the progression of his colleagues through Fitz's glasses. Fitz noticed two men staring at them and supposed that they were working for Radcliffe. Approaching them, they were greeted by Anon, Radcliffe's assistant, who asked them if they had made an appointment.

Upon learning that they were willing to show their technology to Radcliffe only, Anon requested that Fitz and Simmons waited at the bar until Radcliffe was ready to see them. There, they briefly cut their communications so that Mackenzie could not hear them and they resumed their interrupted conversation about moving further in their relationship. Fitz compared the fact of having sex with Simmons to a singularity, like in transhumanism or in a black hole. Simmons found the metaphor both lovely and terrifying, and the two agreed that their best option was to stop thinking about it and simply doing it.

Anon came back to them and invited them to follow her in order to meet Radcliffe. Fitz and Simmons were brought to a small operation room where they were asked to surgically implant the cybernetic eye on a patient in order to demonstrate the efficiency of their technology. They discussed the matter with Mackenzie and resolved to follow Anon's instructions. However, before doing the surgery, Simmons noticed that the eye they were supposed to replace was not of human origin but was instead an avian prosthetic eye. The patient they were supposed to operate was actually Holden Radcliffe himself.

Fitz and Simmons presented their technology to Radcliffe, who recognized it as similar to the one used by Cybertek to control their soldiers through explosives implanted in the eye. Fearing that Fitz and Simmons were from HYDRA, Radcliffe ordered Anon to generate an EMP to disable their communications. Distraught, Fitz and Simmons informed Radcliffe of Hive's existence and his ability to infect Inhumans. However, before they could develop, Radcliffe's guards came across the room and tried to take them out. Fitz managed to knock one guard out and explained to Radcliffe that he was the only one who could save Daisy Johnson while Simmons was taken out.

Just as Fitz mentioned her, Johnson blew up the door of the operation room and proceeded to kidnap Radcliffe with the assistance of Alisha Whitley. Fitz tried to stop them, but Johnson used her powers to throw him against the wall. Johnson then smothered Fitz with her powers and demanded that S.H.I.E.L.D. stopped trying to rescue her, stating that she had finally found a family with Hive and that she was willing to hurt any S.H.I.E.L.D. agent who would come near her. Releasing a hardly breathing Fitz, Johnson finally threatened him to kill him if he came for her again before leaving the club.

Fitz returned to the hotel room, where Simmons was awaiting him. Simmons told him that Mack was busy at the Quinjet they used to come to Romania, so they were alone in the hotel room. Fitz, putting in practice what he and Simmons had discussed in the club, kissed Simmons and the two finally had sex, taking a great leap forward in their relationship.

Searching for a cure
Fitz and Jemma Simmons kept trying to elaborate a cure for Hive's infection. They developed an antitoxin which was shown to fight the parasites, but it was also potentially fatal to the immune system. Fitz insisted that it was worth testing. Lincoln Campbell, ready to do anything to help Daisy Johnson, offered to be their Guinea pig. However, Simmons deemed it too dangerous and they had to call for Phil Coulson in order to make a decision one way or the other. To Simmons, Campbell was only willing to try the antitoxin because he was a "lovesick fool trying to make a grand gesture". Fitz, possibly identifying with that description since he had risked his life on multiple occasions to save Simmons, thought that there was a slight chance that it could work. However, Coulson refused that Campbell received the antitoxin and ordered Fitz and Simmons to look for another solution.

Fitz went to find Simmons at the Playground's cafeteria, worried that their disagreement might affect their relationship in private. Simmons reassured him, saying that she did not want a boyfriend who agreed to anything she could say (since she already had that kind of boyfriend). Both agreed that they should not let their disagreements at work endanger their newfound love story. The pair jokingly talked about their time at the S.H.I.E.L.D. Academy on their way back to the lab, only to find Campbell who had seized a syringe and injected himself with the antitoxin. Fitz and Simmons rushed at him but Campbell, on the verge of fainting refused that Simmons gave him a drug to counter the effects of the antitoxin.

Fitz attended to an exhausted Campbell, blaming him for disobeying Coulson and for causing malfunctions in the lab's equipment, since Campbell's electric powers burst out when he injected himself with the antitoxin. Fitz then prepared Campbell so that Simmons could perform a brain biopsy to test the effects of the antitoxin. Fitz and Simmons soon had another patient to take care of : Alphonso Mackenzie had been wounded by Daisy Johnson in an attempt to bring her back to S.H.I.E.L.D. Coulson's team thus learnt of Hive's plans : turning all humans into Inhumans who would serve him while he took over the world.

Hunting Subversives
"You know, my father always said you have to have trust to be betrayed. Treat this mole like a cancer." "I'll cut it out myself." "Well, you failed before. Never forget how it felt at Cambridge."

- The Doctor and Melinda May

Personality
"It's like magic. But, it's– it's science."

- Leo Fitz

Like his best friend Jemma Simmons, Leo Fitz is known to be an attractive nerd on his profile for S.H.I.E.L.D., though he is somewhat socially awkward. Fitz also has a strange affinity for monkeys. He also has a great sense of humor, teasing Ward behind his back (in a mockery Southern accent), and planning to prank Skye. He is also a good actor, and easily impersonates an American tourist.

In spite of his lack of combat skills, Fitz impressed the more experienced Ward with his remarkable bravery and quick thinking during their mission together in South Ossetia. Fitz believes deeply in the friendships he creates: being upset when Skye appears to have been secretly working with Miles Lydon, actually crying when John Garrett revealed himself as HYDRA , as well as having a rare angry fit and emotional breakdown when Ward was revealed to be a murderer and a HYDRA mole. In return, Fitz is very loyal to his friends, is miserable when he was unable to save Skye from Quinn, and trusts Simmons with his life. Another instance of his loyalty was his refusal to serve Gonzales, deciding to leave rather than betray Coulson.

While Fitz is devastated at Ward's betrayal, he is the only one on the team that still insists that Ward is redeemable, as Fitz believes that people are never "born evil." He is the only one who still tries to reason with Ward and implores him to let Garrett die and abandon HYDRA. Despite that, Fitz later on became very bitter against Ward after he dropped him and Simmons into the ocean to die and for betraying the team, even going on to torture him by suffocating him inside a cell as he did him, and later, attack him. However, Fitz is also very forgiving and understanding of others' problems, shown when he quickly forgives Skye for being so secretive about Miles Lydon, claiming that everyone "makes mistakes." He also instantly forgives Coulson for knocking him out with a punch, understanding the situation. As Simmons grows closer to Triplett, Fitz remains suspicious of him, though he does learn to trust him later on.

Fitz also tends to go through with his promises and threats: he promised Garrett that he would suffer for what he had done, and he (Fitz) plans to be a "very big part of that." By electrocuting and nearly assassinating Garrett shortly thereafter, Fitz manages to keep his word.

The brain damage Fitz suffered has caused him to become withdrawn after Simmons opted to be a part of an undercover mission. Fitz had her as an imaginary friend and frequently talked to her, claiming that those conversations calmed him. Billy Koenig had replaced him in many aspects, raising Fitz's jealousy. No one other than Skye and May interacted with him until Alphonso Mackenzie approached him, creating a new friendship between the two.

Since nearly losing Simmons to the Kree Monolith, Fitz has exhibited a tougher and more determined personality. His actions often put himself directly in harm's way, in order to protect those he loves. In order to find a way to get Simmons back, Fitz traveled to Morocco and negotiated with terrorists, risking his own life for a piece of parchment with the secret of the Monolith written on it. Once he returned to the Playground, he found out that the only word on the parchment is "Death". In his desperation, Fitz blasted the Monolith's container open with a shotgun and started beating on the rock furiously demanding that it swallow him.

Whilst inside the Framework Fitz's personality was radically different to the point where he was the polar opposite from who he was in the real world. Ruthless, cruel, cold and sadistic and claiming to enjoy torturing people who Hydra would capture. "The Doctor", as he was nicknamed, was willing to use his intelligence and scientific ability to further promote Hydra's ideals, developing an agonizing experiment to find out an Inhuman's powers without triggering Terrigenesis.

Abilities
"I'm trapped in here! That's not possible! What did you do?!" "Science, biatch."

- Gordon and Leo Fitz


 * Genius Level Intellect: Fitz has become a very well known agent in the S.H.I.E.L.D. tech community for his technological expertise. Grant Ward's attempt to kill him damaged his temporal lobe, and he displays as a result, a difficulty remembering or explaining words. However, this condition has not affected his intelligence, and Fitz continues being a genius.
 * Master Engineer: Fitz has designed and created many of the equipment commonly used by S.H.I.E.L.D. agents, including the Night-Night Guns and I.C.E.R.s, the Mouse Hole, the Magic Window. He has also created many of the tools used for analysis and scientific work, especially the D.W.A.R.F.s, the Golden Retrievers, the Full-Spectrum Goggles or the Magic Window. The sensitive nature of many mission has made him to develop devices against the clock that needed to be adapted to the parameters of each mission. His expertise also extends to artifacts of Asgardian origin, as his previous experience with the Berserker Staff allowed him to fully repair Lorelei's Asgardian Collar, greatly impressing Sif.
 * Multilingualism: Fitz is able to speak some Arabic and to read Hebrew. He spoke Arabic when he confronted gangsters in Morocco to get to Yusef Hadad. When Fitz opened the scroll casing he had taken from him, he was instantly able to identify the symbol on the scroll as the Hebrew word for "death". However, he did not know that the word also had the meaning "death by punishment".
 * Marksman: Fitz was taught how to handle a handgun, and he resorted to use them to repeatedly shot Hive while possessing Will Daniels' body on Maveth, or to kill Giyera using a Cloaked Gun.
 * Expert Combatant: When Fitz first joined Coulson's Team, he was not a capable fighter. However, through his years of training with the team after joining, he became an adept combatant, being able to fight against a Primitive with great skill.

Weapons

 * : The SIG Sauer P226 pistol is the standard sidearm carried by S.H.I.E.L.D. Tactical Agents. Fitz grabbed one of these weapons from one of the HYDRA operatives infiltrated into S.H.I.E.L.D. and used it to kill another before he could kill Melinda May during the Battle at the Hub.
 * : The Smith & Wesson M&P pistol is the standard sidearm carried by S.H.I.E.L.D. agents. Fitz was issued one when he was on the run from the S.H.I.E.L.D. faction led by Robert Gonzales, together with Phil Coulson and Lance Hunter.
 * : Fitz grabbed the compact version of the Smith & Wesson M&P standard pistol inside Castillo San Cristóbal in Puerto Rico to threaten Alphonso Mackenzie, who had been possessed by the Kree City and attacked his teammates to protect the city.
 * : Fitz obtained this handgun from a backpack carried by one of the HYDRA operatives that took him to Maveth. He used it when he discovered that Will Daniels had died, and Hive had possessed his corpse. Despite Fitz shot him many times, the Inhuman managed to survive all the shots.
 * : Fitz attempted to use one of these submachine guns against Giyera when he managed to escape containment inside Zephyr One and began to took over the plane. However, before he could shoot at him, Giyera easily took the weapon out of Fitz's hands.
 * : Fitz took a Mossberg 500 Cruiser from the arsenal in the Playground to break into the sealed room where the Monolith was being kept, in a desperate attempt to understand what happened to Jemma Simmons when she was swallowed up by the artifact.
 * : Fitz shot a flare with this gun towards the portal to Maveth when it was activated inside the HYDRA Castle. Jemma Simmons saw the flare, and went towards the flare, managing to return to Earth but leaving Will Daniels behind.
 * : Fitz obtained this handgun from the backpack carried by one of the HYDRA operatives that took him to Maveth. He used it against Will Daniels' corpse, who had possessed by Hive, as shots with a Glock 17 pistol proved to be harmless. The flare made Daniels' corpse to burn, leading Fitz he had killed the creature.
 * Night-Night Pistol: Leo Fitz designed the pistol version of the Night-Night Gun for his teammates, but he also began to carry two of them during his field missions with the rest of his team. Fitz used it to repeatedly shot at the already unconscious member of the Cybertek security team that attacked Jemma Simmons in a train in Italy, leaving the gun with an unconscious Simmons to protect herself once she woke up.
 * Overkill Device: Fitz modified the Overkill Device he was sent to deactivate in South Ossetia, and used it as a handheld weapon to disarm the separatists that were about to attack him and Grant Ward.
 * Destroyer Armor Prototype Gun: Under Phil Coulson's explicit orders, Fitz procured and fired the Prototype Gun against Vin-Tak, a Kree who was fighting Bobbi Morse when he tried to kidnap Skye due to her status as an Inhuman.
 * Cloaked Gun: Fitz used this gun to kill Giyera.

Other Equipment

 * D.W.A.R.F.s: Fitz often used the D.W.A.R.F.s in order to analyze and retrieve forensic data during his field missions, such as in the Centipede laboratory in Los Angeles, the temple where an 0-8-4 was located in Peru, the StatiCorp facility in Utah and even the Kree City under Puerto Rico. He also used them to try to stop criminals Vanchat and Marcus Daniels.
 * Localized EMP Device: Fitz retrieved a Localized EMP Device from the Hub and carried it during his dangerous mission to South Ossetia, using it to force a blackout and gain a local mob's trust by fixing it.
 * MAG Pouch: Fitz carried a MAG Pouch during his dangerous mission to South Ossetia, using it to adhere to the underside of a track and enter a separatist compound with Grant Ward.
 * Magic Window: Fitz carried a Magic Window during his dangerous mission during his dangerous mission to South Ossetia, using it to see through the walls of the separatist compound.
 * Spectrographic Analyzer: Fitz resorted to the use of an Spectographic Analyzer to determine the origin of each and every piece of debris found after the Battle of Greenwich.
 * Golden Retrievers: Fitz has used his Golden Retrievers in order to track individuals over a relatively great distance, such as tracking Tobias Ford in Utah or Deathlok in Florida.
 * Tracker: Fitz intended to use a Tracker on the package that Cybertek was delivering to Ian Quinn, but he ended up using it to inform the rest of his team about his and Skye's location in Ian Quinn's Villa.
 * Mouse Hole: A device created by Fitz that was not mass-produced, but kept by S.H.I.E.L.D.'s highest agents, such as Nick Fury and Maria Hill. He kept one for himself, and used it to cut a hole through the Bus and infiltrate the Hub.
 * Cigarette Laser: Fitz tried to demonstrate that the items of the Howling Commando Gear were more than they appeared, and started to pretend he was smoking the Cigarette Lasers. However, the only thing he managed to do was to set the drapes on fire.
 * Quarter Walkie-Talkie: Fitz and Antoine Triplett shared a pair of Quarter Walkie-Talkies as they investigated John Garrett's headquarters in Cuba, leaving it in the Bus and allowing the rest of his team know that the plane had returned to the United States of America.
 * EMP Joy Buzzer: Fitz used the device against John Garrett, damaging his cybernetic prosthesis and bringing him to the brink of death.
 * Forensics Scanner: A forensics device used in the investigation of the man that battled Lady Sif in Portugal.
 * Three Dimensional Scanner: Fitz used Three Dimensional Scanner to analyze the remains of a wall that Lash had disintegrated in order to escape from Lori and Shane Henson's apartment.
 * Backscatter Glasses: Fitz used the Backscatter Glasses during the mission to find Holden Radcliffe.

Fitz-Simmons Designs
"I'm engineering, she's bio-chem."

- Leo Fitz

Family

 * Grandmother
 * Alistair Fitz - Father
 * Alistair Fitz - Father (Framework)
 * Mother

Allies

 * S.H.I.E.L.D. (First Incarnation) (Former Relationships)


 * Nick Fury - Director
 * Maria Hill - Deputy Director
 * Victoria Hand † - Superior Officer
 * Felix Blake - Colleague
 * Eric Koenig † - Colleague
 * Billy Koenig - Colleague
 * Jazuat - Colleague
 * Davis - Colleague
 * Garrett's Team - Colleagues
 * John Garrett † - Friend
 * Antoine Triplett † - Rival and Friend
 * S.H.I.E.L.D. Academy of Science and Technology
 * Anne Weaver - Former Teacher and Friend
 * Franklin Hall - Former Teacher
 * Professor Vaughn - Former Teacher
 * Sally Webber - Fellow Cadet
 * Coulson's Team - Teammates
 * Phil Coulson - Team Leader and Friend
 * Jemma Simmons - Best Friend and Girlfriend
 * Melinda May - Friend
 * Skye - Friend
 * S.H.I.E.L.D. (Second Incarnation)


 * Phil Coulson - Colleague, Former Director and Friend
 * Jeffrey Mace † - Director
 * Melinda May - Colleague
 * Jemma Simmons - Colleague, Best Friend, and Girlfriend
 * Daisy Johnson - Colleague, Friend and Temporary Enemy
 * Antoine Triplett † - Colleague and Friend
 * Alphonso Mackenzie - Colleague and Good Friend
 * Isabelle Hartley † - Colleague
 * Idaho † - Colleague
 * Billy Koenig - Colleague
 * Sam Koenig - Colleague
 * Michael Peterson/Deathlok - Enemy (while under HYDRA Coercion) turned Colleague and Friend
 * Robert Gonzales † - Enemy turned Ally
 * Anne Weaver - Former Teacher and Colleague
 * Anderson - Colleague
 * Nathanson † - Colleague
 * Burrows † - Colleague
 * Davis - Colleague
 * Navarro - Colleague
 * Flynn - Colleague
 * Crawford - Colleague
 * Morales - Colleague
 * Secret Warriors - Colleagues
 * Lincoln Campbell †
 * Elena Rodriguez
 * May's Team - Colleagues
 * Piper
 * Prince
 * Akela Amador - Enemy (while under HYDRA Coercion) turned Ally
 * Elliot Randolph
 * Sif
 * Lance Hunter - Former Colleague and Friend
 * Bobbi Morse - Former Colleague and Friend
 * Andrew Garner/Lash † - Ally and Temporary Enemy
 * Joey Gutierrez - Former Colleague
 * Advanced Threat Containment Unit - Situational Allies
 * Rosalind Price †
 * Glenn Talbot
 * Luther Banks †
 * Robbie Reyes/Ghost Rider - Savior
 * HYDRA (Framework) - Employers
 * Madame Hydra - Director and Lover
 * Melinda May - Subordinate

Enemies

 * Milton
 * HYDRA
 * Grant Ward † - Former Teammate and Friend
 * Jasper Sitwell † - Former S.H.I.E.L.D. Superior
 * Daniel Whitehall †
 * Sunil Bakshi †
 * Centipede Project
 * John Garrett † - Former S.H.I.E.L.D. Superior
 * Ian Quinn
 * Kaminsky
 * Raina †
 * Giyera † - Victim
 * Gideon Malick †
 * Camilla Reyes - Ally turned Enemy
 * Cybertek
 * Carlo Mancini †
 * Agent 33 †
 * Afterlife Inhumans
 * Jiaying †
 * Gordon † - Victim
 * Lorelei - Enemy turned Enthraller
 * Vin-Tak
 * Calvin Zabo - Enemy and Situational Ally
 * Yusef Hadad
 * Watchdogs
 * Felix Blake - Former Colleague turned Enemy
 * Dallas Wyatt
 * Watchdog Oscar - Attempted Killer
 * Briggs
 * Chinatown Crew
 * Hive †
 * Primitives †
 * O'Brien - Colleague turned Enemy (brainwashed)
 * Frederick † - Attempted Killer
 * Eli Morrow †
 * Holden Radcliffe † - Friend and Colleague turned Enemy
 * Life-Model Decoys
 * Aida - Ally turned Enemy
 * Holden Radcliffe (Life-Model Decoy) † - Victim
 * Melinda May (Life-Model Decoy) †
 * Inhumans (Framework)


 * Vijay Nadeer - Captive and Test Subject
 * Skye - Former Subordinate turned Prisoner
 * Agnes Kitsworth † (Framework) - Victim
 * Jemma Simmons (Framework)
 * S.H.I.E.L.D. (Framework)
 * Patriot †

Trivia

 * Fitz is apparently a fan of the long-running, British Sci-fi television show,  as he has a model of the Doctor's beside his bed.
 * Fitz has a distaste of corpses contaminating his work space after Simmons left a liver from a dead cat she was working on next to his lunch.
 * Fitz is the first and only known person that Agent Melinda May has pranked after she became grim and seemingly unemotional.
 * Fitz greatly impressed Lady Sif herself, who admitted that he was "quite clever."
 * Fitz can do a perfect American accent, due to watching a lot of American TV in his childhood. He also does a mockery Southern accent while teasing Ward behind his back.
 * Fitz is the first member of Coulson's team that almost kills the "Clairvoyant", John Garrett. Thus, Fitz becomes, quite possibly, the one Garrett hates the most, since the latter immediately ordered Ward to kill him.
 * Fitz's favorite sandwich is: prosciutto, buffalo mozzarella, and a touch of pesto aïoli on what looks like a baguette.
 * Fitz doesn't have any ex-girlfriends, which means that prior to Simmons, he has never had a romantic relationship with a woman.
 * Fitz along with Simmons took History of S.H.I.E.LD, NeuroBiology and ChemLab at Sci-Tech.
 * Fitz as part of a prank, tells Skye she needs at least 2 semesters of Holographic Engineering to be able to touch the Holotable.
 * During his Lie Detector test, the one item Fitz would choose if he was stranded on a desert island would be Simmons.
 * Fitz's favorite thing in the world is Jemma Simmons.

Behind the Scenes

 * The relationship between Fitz and Jemma Simmons is based on the relationship between Jed Whedon and Maurissa Tancharoen.
 * Fitz's obsession with monkeys was inspired by Iain De Caestecker's real life love of monkeys.
 * Due to his popularity, Leo Fitz was introduced into the main Marvel Comics universe.
 * Fitz also appeared on the animated show Ultimate Spider-Man.