The setting is a New Year's cruise from Europe to Istanbul, where an English couple, Nigel and Fiona (Grant, Scott-Thomas), are planning to fly to Bombay as they celebrate their seventh wedding anniversary.

The film opens with Nigel and Fiona on the deck of the ship when they encounter an ill French woman, Mimi (Seigner), whom they lend a hand. Later, Nigel goes into the bar, where he sees Mimi performing an exotic dance on the stage. She then sidles up to Nigel for a drink, and while he attempts to make a few pleasantries, she insults him. Then, as Nigel heads back to his room, he is confronted by Oscar, an American in a wheelchair (Coyote), who insinuates that Nigel has his eye on Mimi. Oscar is Mimi's husband, and as he points to his legs, he says that, "She did this."

Most of the rest of this very long movie (two hours, 19 minutes) has Oscar relating to Nigel the sordid story of his life with Mimi, in vividly descriptive sexual detail: A failed writer in Paris, Oscar meets and becomes obsessed with Mimi, as their affair becomes more kinky and dangerous. Finally, Oscar burns out and Mimi becomes the obsessed party, while he starts being quite cruel to her. Ultimately, however, they will switch places again.

There are lots of symbols and metaphors here, but the one that seemed most accurate was when, at three different places in the film, three different people vomit. You may feel similarly inclined.

"Bitter Moon" is rated R for violence, sex, nudity, profanity and vulgarity.