Keira Knightley's "The Jacket" co-star, Adrien Brody, had to ply her with vodka before shooting an explicit scene with her, because Knightley found acting her first sex scene unnerving.

"It helped, but doing these scenes feels completely unreal. You get on with someone and all of a sudden you're naked and away with it," Femalefirst quoted the "Pirates of the Caribbean" beauty.

The svelte actress, however, refused to strip completely.

"You're not going to see my arse! The top half is fine but the bottom half isn't," she told the director clearly.