Labyrinth is a historical television miniseries based on the 2005 novel of the same name by Kate Mosse . Sebastian Stan ( born August 13 , 1982 ) is a Romanian-American actor , known for his role as Bucky Barnes / Winter Soldier in the Marvel Cinematic Universe . On television , Stan portrayed Carter Baizen in Gossip Girl , Prince Jack Benjamin in Kings , Jefferson in Once Upon a Time , and T.J. Hammond in the miniseries Political Animals . In 2015 , he co-starred in Jonathan Demme 's Ricki and the Flash , Ridley Scott 's The Martian , and Bryan Buckley 's The Bronze . The Last Templar is a four-hour Canadian miniseries , based on the 2005 novel The Last Templar , which aired in the U.S. on January 25 and 26 , 2009 , starring Mira Sorvino , Scott Foley , Victor Garber , Anthony Lemke , Kenneth Welsh , Danny Blanco Hall and Omar Sharif .
Sebastian Stan only appears in Canadian miniseries.