These Avengers appear in the coming film — and all have appeared in previous films — but they all have decades-long histories in Marvel comic books. Here's a look at their stories.
Who is he? Wearing an advanced suit of weaponry and armor, Tony Stark is Iron Man.
In the films: After being captured in the Middle East in “Iron Man,” the rich and brilliant Stark builds a suit of armor to escape. Later, he builds an even more advanced suit to fight off terrorists. He's the first person S.H.I.E.L.D. spy agency leader Nick Fury recruits to be an Avenger. He fought off Whiplash in “Iron Man 2.”
In the comics: Iron Man was a founding Avenger when he randomly teamed up with Thor, Ant Man, Wasp and Hulk. In the comics, Stark has built countless suits and has battled alcohol addiction.
First appearance: “Tales of Suspense” No. 39, 1963
Who is he? A big, green wrecking machine.
In the films: “Incredible Hulk” shows Bruce Banner on the run from government agents trying to capture him and do research on his super-strength.
In the comics: Bruce Banner was exposed to gamma radiation and, when he gets angry, turns into the Hulk. The Hulk has been smart, stupid, green, gray and even red.
First appearance: “Incredible Hulk” No. 1, 1962
Who is he? The Norse god of thunder.
In the films: In “Thor,” the thunder god fights battles with frost giants in Asgard, goes to Earth where he loses his powers (and his magic hammer) and fights with his brother, the trickster Loki.
In the comics: Thor is banished to Earth, where he lives as respected doctor Donald Blake. When Blake taps his cane on the ground, it becomes the magic hammer Mjolnier and Blake becomes Thor. Loki confronted Thor, who teamed up with other heroes to defeat him, and the Avengers were born.
First appearance: “Journey Into Mystery” No. 83, 1962
Who is she? A secret agent highly skilled in seduction and assassination.
In the films: She works for Tony Stark in “Iron Man 2,” but is really a secret agent for S.H.I.E.L.D.
In the comics: Natalia Romanova started out as a bad girl working for the Soviet KGB. She eventually defected to the United States and began working for S.H.I.E.L.D. and the Avengers.
First appearance: “Tales of Suspense” No. 52, 1964
Who is he? A deadly-accurate archer with an arsenal of special (exploding, heat-seaking, etc.) arrows.
In the films: In “Thor,” the god of thunder breaks into a government facility run by S.H.I.E.L.D. In order to stop him, S.H.I.E.L.D. agent Clint Barton grabbed a bow instead of a gun.
In the comics: At first, Hawkeye was seduced by Black Widow into attacking Iron Man. He later regretted the decision and made an effort to join the Avengers.
First appearance: “Tales of Suspense” No. 57, 1964
Who is he? Clad in red, white and blue, he's a leader of the Avengers.
In the films: In “Captain America: The First Avenger,” the story followed his fight against the technology-loving, mad-genius Nazi, Red Skull.
In the comics: The army recruits scrawny Steve Rogers and gives him a super soldier serum that turns him into Captain America. Cap wasn't a founding Avenger, but was one of the team's first recruits.
First appearance: “Captain America Comics” No. 1, 1941