The new dramatic thriller 'Black Swan' features a steamy sex scene between stars Mila Kunis and Natalie Portman, which is something Kunis says she knew would grab headlines.

"We knew it was going to attract attention," she tells Parade magazine. "We were just hoping that people would walk away after seeing the movie not just isolating in their memory that scene when we have sex."

Kunis says the scene is essential to the film.

"I think it's important to the story," she says. "It wasn't done for shock value, but we weren't looking forward to it."

'Black Swan' is directed by Darren Aronofsky and hits theaters Friday.

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