Four Weddings and a Funeral is one of my favorite romantic comedies, but I always find the ending a bummer. I think Hugh Grant should've wised up and chosen Kristin Scott Thomas, not the lame American. When Bitter Moon started rolling we had a good laugh, because there were Hugh Grant and Kristin Scott Thomas, married. I wonder if Mike Newell's casting was a wink at this film, which had come out two years earlier. Thomas's character is even named Fiona in both films.
The cast was basically the only thing that I really liked about Bitter Moon. Grant is never better than when he's looking uncomfortable, and he looks plenty uncomfortable here. Kristin Scott Thomas is quite effective as his wife. Peter Coyote is something of a revelation: I'd only known him as a counterculture figure (he pops up in everything I read about early Dead and Airplane) and a narrator of PBS documentaries, but he's got a great sick charisma here. Even the minor roles are well cast: Victor Banerjee's gentlemanly Mr. Singh has a touch of the sinister enigma about him, and Stockard Channing's cameo as Oscar's agent is key.
As for the movie itself? I found two zealous, almost convincing defenses of it here and here. I'm willing to concede that most of the ideas those essayists discuss are in the movie (incidentally, I find it interesting that those essayists seem to disagree on the nature of the ending: is Fiona and Mimi's tryst part of Oscar's ambush of Nigel, or is it Mimi's final revenge on Oscar?).
I just wish the ideas had been presented in a more persuasive movie. ...But now that I try to set down what I thought were flaws in the film, its presentation, its characters, whatever, I find I'm deleting everything I write, because most of what I thought was a flaw was actually explained by the kind of story Polanski was trying to tell, and the almost cruel detachment with which the story had to be told. Hmm. So what is it I want to say about this movie? I think I got it (not as eloquently as the two essays I linked to above, to be sure), intellectually, but I didn't particularly enjoy it.