Zemo is a Nazi scientist and the founder and original leader of the Masters of Evil, and is commonly depicted as one of the greatest enemies of Captain America and the Avengers.

The character has been adapted into numerous forms of media, having most notably been voiced by Robin Atkin Downes in The Avengers: Earth's Mightiest Heroes animated series.

Heinrich's intelligence was only matched by his sadism, as he routinely tested his deadly weapons on innocent people, both prisoner and civilian, inside the Third Reich.

This ultimately came to a head during an early encounter with the Howling Commandos, when Zemo decided to test an experimental death ray cannon on a nearby German town.

In an attempt to regain a level of anonymity, Zemo began wearing a reddish-pink hood over his face as he continued to build weapons for the Nazis.

Adopting a new costume, Zemo went from becoming a normal, if not infamous, Nazi scientist to become an active field agent for the Third Reich, leading German troops into combat and espionage missions.

At this point the plane would do them no good, but Red Skull made sure that this knowledge was leaked to Captain America and young sidekick Bucky so as to ensure that Zemo would be caught, thus ridding him of his rival once and for all.

[4] Believing that he had killed his rival at long last, Zemo fled to South America as Hitler and the Nazis fell and World War II ended.

[5] To that end, Heinrich formed the original Masters of Evil to serve as a villainous counterpart to the Avengers; the other founding members included the Black Knight, the Melter, and the Radioactive Man who were gathered by his pilot.

He tried to have Adhesive X spread over New York, but the Teen Brigade seized Zemo's pilot, preventing him from speaking, then tied him up to stop him causing trouble.

His ray gun's shot hit a rock, starting an avalanche that killed him, and Captain America felt that Bucky's death had finally been avenged.

[15] While he does not physically appear, his voice is heard in collectable diary entries, which reveal his family's history and his alliance with the Red Skull to awaken the Sleeper beneath Castle Zemo.