Leo Fitz

"And I should be there with them, but I can't be because of you, because of what you did to me!... I'm damaged!"

- Leo Fitz to Grant Ward Leopold "Leo" Fitz is a Scottish-born S.H.I.E.L.D. agent and scientist. He is a brilliant engineer, and inseparable from his research partner and best friend, Jemma Simmons. He, along with Simmons, was recruited to Coulson's Team by Melinda May and worked with them on all of their missions. While on the team, Fitz became very good friends with teammate Grant Ward.

During the S.H.I.E.L.D. Civil War, he became jealous of Simmons' friendship with Agent Antoine Triplett. 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, resulting in several arguments with Simmons and the rest of the team. Fitz was captured by HYDRA along with Simmons, and met Ward again.

When Ward was ordered to kill them, Fitz fruitlessly begged Ward to have mercy, and was dumped into the ocean in the Bus's Medical Pod with Simmons. They survived the fall, but were trapped on the ocean floor. Fitz devised a plan using the pod's oxygen bottles to get them out of the pod and to safety, but there was only enough oxygen for one, and while confessing romantic feelings for Simmons, he saved her. However, this resulted in him spending a long period of time without oxygen, causing brain damage.

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, 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. After 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.

When Simmons was infected with an alien virus passed along from a Chitauri Helmet, Fitz risked contamination and death in order to help save his 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 conjured up 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 Simmon's 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 Simmon's 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.

He 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. When he did, he took it 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.

S.H.I.E.L.D. Civil War
"At least we still have each other." "Good, 'cause the last thing I want is for things to change." "Fitz...it's too late for that."

- Jemma Simmons and Leo Fitz

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
"You need to accept the truth, Fitz. He doesn't care about us, about anybody!"

- Jemma Simmons

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.

Eventually, Coulson's Team found John Garrett and Grant Ward in Havana, Cuba. Grant Ward found Fitz and Jemma Simmons spying on them 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 fatally injured Garrett. Fitz begged Ward to let Garrett die, but Garrett told Ward to kill Fitz. Fitz and Simmons became cornered in a Medical Pod and Ward ejected them 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 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 get out of his coma, but months later Fitz still experienced damage to parts of his brain that still hadn't 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.

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 May, Triplett, and Skye to steal a Quinjet when he deemed that Fitz was incapable of the job.

However, Fitz was able to recognize the Overkill Device as a way to disrupt Carl Creel's powers, helping Alphonso Mackenzie to modify it in order to stop Creel. This cooperation started a friendship between the two.

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 that held Grant Ward. Ward attempted to convince him that he was not trying to kill Fitz and Simmons, but find a way for them to escape John Garrett's kill order. 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.

When Coulson met with Fitz privately after this incident, he 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 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.

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 weren't 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. Fitz decided to participate and began talking about 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 lets go of the imaginary Jemma, when the real Jemma Simmons returns 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. Mackenzie 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 Mackenzie 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 Mack 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 can't truly be erased; 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 City Blueprints 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 rebuilting 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 City Blueprints could be found; he admitted that he was able to do the job in under seven and half minutes, not six, when using one hand. The team entered the station, nonetheless. 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 City Blueprints. 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 was he 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 Mack 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 haz-mat 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.

Personality
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.

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. Thus, Fitz is also very forgiving and understanding of others' problems, shown when he quickly forgives Skye for being so secretive about Miles Lyndon, 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 not to be a part of the new S.H.I.E.L.D. Fitz has her as an imaginary friend and frequently talks to her, claiming that those conversations calms him. Billy Koenig has 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.

Abilities
"It's like magic. But, it's-- it's science."

- 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.

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

- Leo Fitz

Family

 * Mother

Allies

 * S.H.I.E.L.D. (First Incarnation) - Allies (Former Relationships)
 * Nick Fury - Director
 * Maria Hill - Deputy Director
 * Victoria Hand † - Superior Officer
 * Felix Blake - Colleague
 * Eric Koenig † - Colleague
 * Billy Koenig - Colleague
 * Dr. Jazuat - Colleague
 * Garrett's Team - Colleagues
 * John Garrett
 * Antoine Triplett
 * S.H.I.E.L.D. Academy of Science and Technology
 * Anne Weaver - Former Teacher
 * Franklin Hall - Former Teacher
 * Professor Vaughn - Former Teacher
 * Coulson's Team - Teammates
 * Phil Coulson - Team Leader
 * Jemma Simmons - Best Friend and Love Interest
 * Melinda May
 * Skye - Friend
 * Grant Ward - Friend
 * S.H.I.E.L.D. (Second Incarnation)
 * Phil Coulson - Director and Friend
 * Melinda May - Colleague
 * Skye - Colleague and Friend
 * Jemma Simmons - Colleague, Friend and Former Love Interest
 * Antoine Triplett † - Colleague and Friend
 * Isabelle Hartley † - Colleague
 * Idaho † - Colleague
 * Billy Koenig - Colleague
 * Lance Hunter - Colleague
 * Alphonso Mackenzie - Colleague and Best Friend
 * Bobbi Morse - Colleague
 * Akela Amador - Enemy while under HYDRA Coercion, now Ally
 * Michael Peterson - Enemy while under HYDRA Coercion, now Ally
 * Elliot Randolph
 * Sif

Enemies

 * Grant Ward - Former Teammate and Friend
 * Raina
 * HYDRA
 * Jasper Sitwell † - Former S.H.I.E.L.D. Superior
 * Centipede Project
 * John Garrett † - Former S.H.I.E.L.D. Superior
 * Ian Quinn
 * Kaminsky
 * Camilla Reyes - Ally turned Enemy
 * Cybertek
 * Carlo Mancini †
 * Lorelei - Enemy turned Enthraller

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 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 only member of Coulson's team that still believes that Ward is redeemable, and not truly evil. He is also the only one that tries to reason with Ward and implores the latter to let Garrett die and abandon HYDRA.
 * 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 he 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.
 * In episode 1x19 "Repairs" Fitz as part of a prank, tells Skye she needs at least 2 semesters of Holographic Engineering to be able to touch the holo-table.

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.