Actress Rachel Bilson was so terrified of filming a sex scene with Hayden Christensen, she drank shots of alcohol to calm herself down.

The former The O.c. star was wracked with nerves before stripping off for new movie Jumper - insisting it goes against nature to simulate sex on a film set.

The 26-year-old says, "I remember Hayden and I were both like, 'Let's drink a shot or something to calm our nerves.'

"Because it's just so awkward I mean, this was a very mild scene compared to the one in The Last Kiss (2006 film), but it was still nerve-wracking."

"I don't think that's ever going to be a comfortable thing for me. It's just something that goes against nature."