Sebastian Stan is a Romanian and American actor. He gained recognition for his role as Bucky Barnes / Winter Soldier in the Marvel Cinematic Universe media franchise, beginning with 2011's Captain America: The First Avenger. He later returned in Captain America: The Winter Soldier (2014), and went on to star in Captain America: Civil War (2016), Avengers: Infinity War (2018), Avengers: Endgame (2019) and The Falcon and the Winter Soldier (2021). On television, he has played Carter Baizen in Gossip Girl, Prince Jack Benjamin in Kings, Jefferson in Once Upon a Time, and T.J. Hammond in Political Animals. The latter earned him a nomination for the Critics' Choice Television Award for Best Supporting Actor in a Movie/Miniseries. In films, he co-starred in Jonathan Demme's comedy-drama Ricki and the Flash and Ridley Scott's science fiction film The Martian. In 2017, he portrayed Jeff Gillooly in the biopic I, Tonya.