Sebastian Stan has signed on to play Bucky Barnes in Marvel's The First Avenger: Captain America.

According to Variety, the character is a key role in the Captain America comicbooks. He's an orphan who discovers Captain America's true identity and partners up with him to fight the Nazis. He later becomes the covert assassin Winter Soldier.

RELATED: Marvel Movies Are 'Crap' According to Iron Man 2 Star Mickey Rourke

Stan's deal includes appearing in multiple films, including sequels to Captain America and other superhero titles such as The Avengers.

Joe Johnston is directing the action adventure which opens in theaters in theaters July 22, 2011.

Production starts this summer.