Filming in Serbia, 80% of the cast and crew got food poisoning and were out for a week recovering. Scott Mechlowicz said they were told the main hospital was bad and that they'd be taken to a good one. It turned out to be a defunct children's hospital that was filthy and eerie, like something in a slasher film. He said the secretary was the person who administered his IV.
During an interview, Paz Vega was asked if she was happy she didn't have to be naked like the other prostitutes in the opening scene. She said, "For me, nudity is natural. When a scene calls for nudity, I don't judge it morally or ethically. I am an actress and do what is called for. This film is about prostitution and I play a prostitute so it would've been appropriate, but there was enough nudity that it would be too much. It wasn't necessary."
Christopher McDonald said in an interview that when he took the role, he knew his wife wasn't going to like him grabbing naked girls' asses in the orgy scene.
Christopher McDonald said he was one of the last people cast for this. Casting director Mary Vernieu, an old friend of his, called him up and told him he'd be great for it. So he read the script and was on a plane flying to Serbia within three days.
Scott Mechlowicz said working with Janet McTeer was amazing. He said, "She's just gorgeous, so to see her with a weapon just makes her that much hotter."