- "Cut off one head, two more shall take its place. Hail HYDRA!"
- ―Heinz Kruger to Captain America
Heinz Kruger was one of HYDRA's top assassins. He successfully assassinated Abraham Erskine under the order of Red Skull, but committed suicide to avoid interrogation after his capture by Steve Rogers.
- "Who the hell are you?"
"The first of many."
- ―Captain America and Heinz Kruger
Heinz Kruger was a HYDRA agent under the command of Johann Schmidt, better known as the Red Skull. When Schmidt heard that Abraham Erskine's Super Soldier Program was creating another subject in America, he dispatched Kruger to assassinate the old scientist and eradicate any evidence of Erskine's work.
Kruger was present during the culmination of Project Rebirth on June 22, 1943, where he was presented as Fred Clemson, a U.S. State Department official invited to watch the results. He was given a lift to the event in Senator Brandt's personal car; once he arrived, he was introduced to Colonel Chester Phillips and sat with the many government officials and generals to watch the experiment.
After Steve Rogers was successfully transformed into America's first Super-Soldier, Kruger used a concealed bomb to destroy the research; in the chaos, Kruger stole the last remaining drops of the Super-Soldier serum and shot Erskine twice in the chest, killing him. Peggy Carter managed to shoot him in the arm; nonetheless, he made his escape through the building, killing several soldiers as he went.
However, Kruger was incapable of stopping Steve Rogers and was forced to retreat from the man who would become Captain America. On his way out, he hijacked two taxis, the first of which was stopped when Peggy Carter shot through the windshield and killed the driver, the second was pursued on foot by Rogers.
Eventually Rogers forced Kruger into a footrace, which Kruger took advantage of by kidnapping a small child from the street, taking him to the docks with the gun to his head. When Rogers pursued, Kruger attempted to shoot him, but discovered he was out of ammunition in his clip, causing him to throw the child into the water below as a distraction. When Rogers checked on the kid, he said he was okay because he could swim, and encouraged him to get Kruger.
With his mission mostly complete, Kruger boarded an advanced submarine, the Fieser Dorsch. It was already submerged and swimming back to Germany, when Steve Rogers appeared outside the cockpit, shattered it and ripped Kruger out, dragging him back out of the water and throwing him onto the docks above. When Rogers attempted to interrogate him, Kruger claimed that he was simply the first of many, and that when you cut off one head, two more grow in its place. Before Rogers could ask more detailed questions, Kruger bit down on a concealed Cyanide Pill in his mouth, killing himself for his cause, saying "Hail HYDRA!".
- Master Spy: Kruger managed to infiltrate into the first Project Rebirth test posing as an United States State Department official by the name of Fred Clemson, mimicking a perfect American accent to match, and making nobody suspicious of him.
- Walther P38: Kruger was armed with the standard Walther P38 pistol which he used to assassinate Abraham Erskine.
- Thompson M1921: Kruger obtained a Thompson submachine gun from the antique store owner that guarded the facility where Project Rebirth was developed, and used it until it ran out of ammo.
- Cyanide Pills: Like every other HYDRA operative during World War II, Kruger had a cyanide pill concealed inside a fake tooth to commit suicide in case he was captured by the enemy. He used his pill when Steve Rogers managed to prevent him from escaping New York City.
- In the comics, Kruger is a Gestapo agent working for the Nazi party instead of an agent of HYDRA, who was killed after accidentally grabbing a live wire during a confrontation against Captain America.