'Paranoia': Liam On 'Intimate' Scenes with Amber

Liam Hemsworth holds his own opposite acting heavyweights Harrison Ford and Gary Oldman in the high-stakes thriller Paranoia, but what seemed to be more difficult for the Aussie hunk was the "intimate" scenes with co-star Amber Heard.

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"Intimate scenes are always pretty scary," Liam tells ET. Of course, neither Liam nor Amber are single, as he's tempestuously attached to Miley Cyrus and she's linked with her former The Rum Diary co-star Johnny Depp. "[On set], you're being intimate with someone in front of a lot of people, and it's hard to let go and just be free in the scene. But Amber's such a great girl and so much fun to work with and she does a terrific job in this film."

In theaters August 16, Paranoia casts Hemsworth as Adam Cassidy, an entry-level employee at the Wyatt Corporation who is coerced by his ruthless CEO Nicholas Wyatt (Oldman) to spy on corporate rival Jock Goddard, played by Ford. A pawn in Wyatt's corporate game, Cassidy soon realizes he's in over his head when his boss will stop at nothing, even murder, to win a multi-billion dollar advantage.

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Directed by Robert Luketic (21, Legally Blonde), Paranoia boasts a supporting cast that includes Josh Holloway, Julian McMahon, Embeth Davidtz and Richard Dreyfuss.