In this movie, there is a lot of nudity, including from Ewan McGregor who spends most of the movie completely naked. When being casted for the role, he was asked "Look, you're going to be completely naked, and we need to be able to shoot anything.". Ewan answered "Thank's okay". Then they asked "Would you simulate sex with a woman?". Ewan said "Yeah, no problem." Then they asked "Would you simulate sex with a man?. Ewan said "Yeah, that's okay.". He got the role!