Dr. Bill Harford (Tom Cruise) spirals out of control in a night filled with debauchery, fantasy and sexual experimentation the likes of which he can't even begin to understand when he discovers that his wife, Alice (Nicole Kidman) has had fantasies of her own. The film has a surreal feel to it as Bill travels through place after place filled with things that are not of his own fantasies, but other people's. He goes to places he can't even begin to understand but finds it all arousing which tosses him even deeper into the dark places in his mind. His activities finally lead him to a masked sexual ball where his whole existence as he knows it is thrown into jeopardy. The threats come quickly as his work unravels. What did he do last night?