Johann Fennhoff and his brother joined the Soviet Armed Forces; Johann as a medic, his brother as a soldier. They were deployed to participate in the World War II campaign to push Nazi forces back from the German town of Finow.
General John McGinnis of the United States Armed Forces wanted the Soviet forces to be able to defeat the Nazis quicker. He knew that Howard Stark was commissioned to create a gas called Midnight Oil that would allow people to work and fight without sleep. McGinnis stole the gas from one of Stark's safe houses and deployed it over the Soviet soldiers. Johann wore a gas mask on the battlefield; his brother did not.
Unknown to McGinnis, Stark learned that Midnight Oil caused symptoms similar to intense sleep deprivation coupled with asphyxiation where ultimately the inhaler of the gas desired to kill those around him, friend or foe. Stark did not want it used.  The Battle of Finow became legendary as dozens of Soviet soldiers were massacred. Though Nazi Colonel Ernst Mueller was given the credit, his troops never fired a shot, finding the Russians already dead having killed themselves. Howard Stark had an underlying feeling of guilt for not being able to find his friend Steve Rogers, after Rogers was lost in icy waters.
Stealing Howard Stark's Weapons
With funding and resources provided from Leviathan, Johann Fennhoff sought out his revenge on Howard Stark for the slaughter of Russian soldiers, including his brother, during the Battle of Finow. Dottie Underwood went undercover and seduced Stark in order to discover where he kept his weapons while, assassins Leet Brannis and Sasha Demidov were hired to steal them. However Brannis betrayed Leviathan and stole the weapons for himself, attempting to sell the Nitramene bombs to Spider Raymond and Gino DeLucia.
Believing that Stark was selling the weapons himself, Chief Roger Dooley made Stark the Strategic Scientific Reserve's most wanted fugitive and sent out teams to find him. Meanwhile Sasha Demidov began assassinating whoever attempted to buy a Nitramine bomb. Eventually Brannis was found by Agent Peggy Carter, after an incident where a Roxxon Refinery was destroyed by Stark's weapons, Demidov found Brannis at the same time and both were killed, however Brannis was able to help Carter find Stark's weapons and hand them over to the SSR, including the Midnight Oil.
With his plans having been changed, Johann Fennhoff devised a new plan to come to America and steal Stark's weapons from within the SSR. Using the Remote Typewriter that had been taken from Sasha Demidov, Fennhoff allowed the SSR to track Leviathan to the Red Room Academy and find him in a prison cell, going by the name Fennhoff and posing as a psychologist for another prisoner named Nikola, he was freed by Jack Thompson and Peggy Carter.
During the resulting firefight with the Russian soldiers guarding him, Fennhoff was forced to kill Nikola when he attempted to make his own escape. However with the assistance of the Howling Commandos, Fennhoff, Thompson and Carter were able to make their escape, despite Commando Junior Juniper and Agent Mike Li being killed in the battle. Having said their goodbyes to the Commandos, Fennhoff was invited back to America to discuss what he knew of Leviathan with Chief Roger Dooley.
Johann Fennhoff informed the Strategic Scientific Reserve of small details of Leviathan, claiming to have very minimal knowledge of them and their workings, denying that they were training female assassins in the Red Room. As he discussed this with Chief Roger Dooley, Fennhoff made a point to step towards the window where he communicated his plans with Dottie Underwood. Knowing that she was his main threat, Fennhoff ordered Underwood to assassinate Agent Peggy Carter.
With time running out, Fennhoff put Agent Yauch under his control and forced him to tell him the quickest exit routes and where Howard Stark's weapons were being kept, although he was informed only Dooley was allowed access to them. Fennhoff ordered Yauch to have one final drink before killing himself by walking in front of a truck, he then updated Dottie Underwood of the need to move forward. Fennhoff took control of Chief Dooley and ordered him to help him find the Midnight Oil, giving him the Stark Heat Vest in exchange before walking out of the New York Bell Company and regrouping with Underwood.
As instructed, Roger Dooley put on the Stark Heat Vest once Fennhoff was gone and locked himself in his office. Regaining control of his mind, Dooley revealed his situation to his fellow officers who tried to find a way to save him. Despite his best efforts, Alex Doobin was unable to find a way to take off the Vest without causing it to explode. With the heat increasing around him, Dooley took Jack Thompson's gun and ordered Peggy Carter to find Fennhoff. He then leapt out of the window seconds before the Vest exploded, killing him but saving his agents.
With the Midnight Oil having been kept in storage for so many years, Johann Fennhoff knew that it needed to be tested before it could be used in their final scheme. Having purchased a baby carriage, Dottie Underwood hid a canister of Midnight Oil in the carriage and walked it into a cinema screening, where she activated it and quickly departed as Fennhoff locked the people inside.
Having been exposed to the deadly gas, the forty six men and women inside the cinema began to attack and brutally murder each other, blinded by pure rage caused by the Midnight Oil. They were found only a few minutes later having all been killed. Peggy Carter, Jack Thompson and Daniel Sousa soon came to investigate and Sousa became affected by the gas, causing him to attack Thompson before being stopped. Sousa recovered and Howard Stark surrendered to the SSR in order to explain what the Midnight Oil was and how it was used during the Battle of Finow.
Johann Fennhoff discussed with Dottie Underwood how the destruction of New York City would be the perfect revenge when they were stopped by Officer Pike for running a stop signal. Fennhoff told Underwood not to draw attention to them and had her sheathe her weapon. He pretended to be Underwood's veteran grandfather as she avoided a ticket. However, Pike had to be captured when he discovered the car was stolen.
Meanwhile Howard Stark returned to New York City where he and Edwin Jarvis surrendered themselves to the Strategic Scientific Reserve, who were still reeling from the death of Chief Roger Dooley. Stark explained to the SSR the history of Midnight Oil and what had happened during the Battle of Finow. Once they worked out that Fennhoff was targeting Stark alone in revenge, Stark volunteered to be used as bait to draw Fennhoff into the open. A press conference was arranged where Jack Thompson would annouce that Stark had been cleared of all charges.
Meanwhile, Fennhoff and Underwood arrived at a warehouse of Howard Stark's that Underwood had visited six months earlier, where they were greeted by a guard. Underwood politely stepped from the car and greeted the man with a smile before she quickly and effectively knocked him to the ground before shooting him twice in the back of the head. When Underwood went to collect Fennhoff, he revealed to her that he had learned of the return of Stark and told her they will go back to the New York City with a new plan to exact their revenge on Stark.
The press conference went underway where Thompson gave a speech to a crowd of journalists announcing Howard Stark's innocence. As Stark stepped forward to give his own speech, the rifle that Dottie Underwood had set up in a nearby window fired just above his head. In the ensuing chaos the brainwashed Officer Pike was able to kidnap Stark after Edwin Jarvis had tried to protect him, Pike then brought him to Johann Fennhoff before being executed. Stark was driven back to his warehouse while Underwood held him at gunpoint and he attempted to flirt with her.
Stark was tortured by Underwood before Fennhoff explained to him why he hated him; he was the inventor of Midnight Oil and, by extension, the killer of his brother. Stark attempted to reason with Fennhoff by explaining that though he created the gas, it was General John McGinnis who dispensed it without his permission. Fennoff asked Stark if he felt the guilt of all the deaths caused by his inventions, and Stark told him that he did. He would not be dissuaded; Fennhoff hypnotized Stark to have him fly a plane through New York's V-E Day anniversary celebration dispersing the gas.
With Howard Stark now completely under Johann Fennhoff's control, he was convinced that he would be able to fly his plane to Captain America's location, believing that New York City was the Arctic where the Captain would be found when he crash landed. While Dottie Underwood stood close by, Fennhoff spoke to Stark over the radio, keeping him under his control as he flew towards Fennhoff's ultimate revenge and the deaths of thousands.
They were interrupted when Peggy Carter stormed in armed with a shotgun and attempted to arrest the pair. Dottie Underwood defended Johann Fennhoff and ordered him to run for safety as she battled the SSR agent. After a prolonged fight Underwood began to mercilessly beat Carter with a baseball bat while continuing to mock her efforts. Carter however was able to gain the upper hand and successfully kicked Underwood out of a window where she fell and hit her head. Despite the fall, Underwood survived and later escaped before she could be arrested.
Now alone with the radio, Peggy Carter began desperately trying to convince Howard Stark that what he was seeing was not real and to turn the plane around, however Stark remained utterly convinced by Johann Fennhoff's illusions and believed he was getting closer to finding Captain America. With Edwin Jarvis flying close behind ready to shoot Stark out of the sky, Carter made a final desperate plea to her friend which successfully broke Fennhoff's control and allowed Stark to return to the base, saving thousands of lives.
Meanwhile Johann Fennhoff was able to knock out Jack Thompson, however he was spotted by Daniel Sousa who ordered him to surrender while he held him at gun point. Fennhoff attempted to use his power over Sousa, telling him that he could help him with his leg and earning the affection of Peggy Carter. Once Sousa was seemingly under his control, Fennhoff ordered him to kill Thompson, which he seemed prepared to do as he raised his gun. However Sousa was secretly wearing earplug and knocked Fennhoff out, as he had not heard a word he had said.
Johann Fennhoff was arrested by Strategic Scientific Reserve New York Bell Company Office branch agents Daniel Sousa and Jack Thompson. He was muzzled so that his power would not be used on the prison guards. He was given a cell to share with HYDRA scientist Arnim Zola, who wanted to learn how Fennhoff's power worked.
Though Peggy Carter stopped Howard Stark from deploying the Midnight Oil gas, Jack Thompson was recognized by President Harry S. Truman as saving New York City. Carter chose not to care about the approval of others; though her associates now respect and admire her for being the actual hero.
- ↑ 1.0 1.1 Agent Carter: 1.05: The Iron Ceiling
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Agent Carter: 1.08: Valediction
- ↑ Agent Carter: 1.04: The Blitzkrieg Button
- ↑ Captain America: The First Avenger
- ↑ Agent Carter: 1.01: Now is Not the End
- ↑ Marvel One-Shot: Agent Carter
- ↑ Agents of S.H.I.E.L.D.: 2.02: Heavy is the Head
- ↑ Agents of S.H.I.E.L.D.: 2.03: Making Friends and Influencing People