Captain America: The Winter Soldier villain Sebastian Stan looked to late actor Heath Ledger as a major source of inspiration.Sebastian Stan "can't compare" himself to the legendary Heath Ledger.The 31-year-old Romanian actor portrays the villain in new Marvel film Captain America: The Winter Soldier.Heath famously portrayed Joker in 2008 Batman picture The Dark Knight, and whilst preparing to depict The Winter Soldier, Sebastian looked to the late star for inspiration."I just always admired his performance and him as an actor," said to Cover Media of Heath, who perished at the age of 28 the same year The Dark Knight was released. "I can't compare myself to anything like that. He is an inspiration. That was his most memorable performance, [the Joker]."Sebastian spoke to Cover journalists Thursday night at the London premiere of Captain America: The Winter Soldier.Whilst onstage he explained his desire to honour the legacies of actors who gave riveting onscreen performances of comic book villains."I think we've all seen in the last decade [how excellent these performances have been]. So for me it's just a responsibility you know," he said."Playing a villain as a character, just look at how these other guys have done it. What can I do to contribute?"Sebastian's first major role was in Black Swan, the Academy Award-winning 2010 thriller about a mentally ill ballerina starring Natalie Portman and Mila Kunis.The rising star also appeared as James Buchanan 'Bucky' Barnes in Captain America: The First Avenger, which was released in 2011.