GOSSIP GIRL regular Sebastian Stan has been cast as Captain America’s sidekick Bucky Barnes in THE FIRST AVENGER: CAPTAIN AMERICA, reports VARIETY. As comic fans know, Bucky is an orphan who learns of Captain America’s secret identity and partners with him to battle the Nazis. Later on in the comics he became assassin Winter Soldier. Stan has signed on for both CAPTAIN AMERICA sequels, as well as the epic AVENGERS flick.

Recently, Marvel named Chris Evans (FANTASTIC FOUR) as their Captain America and Hugo Weaving as the villain Red Skull. Joe Johnston is directing.

Paramount will release the film on July 22, 2011.

Stan can also be seen in the sci-fi comedy HOT TUB TIME MACHINE in theaters now.