Game of Thrones star Kit Harington sits with ET's Nancy O'Dell to talk about one of the most incredible moments in human history -- and what he's wearing under that Gladiator kilt in his epic new thriller, Pompeii!
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"I wore a jockstrap for a solid four months, and I got too used to it, actually -- can't live without a jockstrap on," quips Kit. "In other things I do I'm always in big, big layers of clothing, so actually one of the appealing things about playing this part was the lack of that. And I was in a warm environment, I wasn't in the freezing cold, so I enjoyed the costume in this [movie]."
In theaters Friday, the epic Pompeii follows Kit's gladiator character, Milo, who finds himself in a race against time to save his true love Cassia (played by Emily Browning), the beautiful daughter of a wealthy merchant who has been unwillingly betrothed to a corrupt Roman Senator. As Mount Vesuvius erupts in a torrent of blazing lava, Milo must fight his way out of the arena in order to save his beloved as the once-magnificent Pompeii crumbles around him. Directed by Paul W.S. Anderson, Pompeii co-stars Carrie-Anne Moss, Jessica Lucas, Jared Harris and Kiefer Sutherland.
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Watch the video for more as Kit explains how he got that crazy six-pack for the film -- and how he's related to real-life royalty!