Sebastian Stan Joins 'Captain America' Cast

'Gossip Girl' actor will play sidekick Bucky in comic book movie, due out in 2011.

First, [movie id="390379"]"Captain America"[/movie] had its villain. Then, it had its hero. Now, that hero has his sidekick. According to The Hollywood Reporter, "Gossip Girl" actor Sebastian Stan has joined the cast of "The First Avenger: Captain America," Marvel Studios' upcoming film about soldier-turned-superhero Steve Rogers.

Stan will play James "Bucky" Barnes, the title character's partner, in the 2011 film. His contract reportedly obligates him to appear as Bucky in "five or six" additional Marvel movies.

The actor joins Chris Evans, who landed the Steve Rogers role earlier this month, and Hugo Weaving, who was reported to be in negotiations to play the film's main villain, Red Skull. Stan was one of many actors allegedly under consideration for the lead role.

In comics history, Bucky was Rogers' teenage sidekick, and he fought alongside Captain America in World War II. Previously believed to have died in the mission that left Captain America frozen in a block of ice, Bucky later reappeared in the modern comics universe as a brainwashed assassin. He eventually regained his memory and took up the mantle of Captain America when Rogers appeared to have been killed.

Before he teams up with Marvel's star-spangled superhero, however, Stan will join "Twilight" alum Ashley Greene and "Harry Potter" villain Tom Felton in the supernatural scare-fest "The Apparition" later this year. He also has an unnamed role in "The Wrestler" director Darren Aronofsky's next project, the ballet-themed thriller "Black Swan."

"The First Avenger: Captain America" is scheduled to hit theaters July 22, 2011.

Check out everything we've got on "The First Avenger: Captain America."

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