What’s the next best thing to scoring arguably the year’s hottest part for a young actor in Hollywood? Scoring the role of the hottest part’s sidekick! Sebastian Stan, best known at this point in his career for playing Carter Baizen on Gossip Girl and dating Leighton Meester in real life, was one of the rumored finalists a few weeks ago for the role of Captain America, which eventually went to Fantastic Four alum Chris Evans. But it seems the casting directors were so charmed by the Romanian-born actor that they found a place for him in the franchise, casting Stan as Bucky Barnes, Captain America’s sidekick, who is a “teenaged orphan†in the comics and joins Captain America in his “Nazi-fighting escapades†after discovering the hero’s identity. Let’s hope for the actors’ sakes there were no Blair/Serena-style catfights in the waiting room, as Evans and Stan are going to be spending a lot of time together: according to insiders, Stan, like Evans, has signed on for “five or six†films in the series. [Heat Vision/HR]