Well, we finally saw Lust, Caution last week.
I found this bbc-review
Ang Lee's follow up to Brokeback Mountain is another tale of forbidden passion, but instead of dewy-eyed cowboys, the lovers are opponents in a deadly game of espionage. In Japanese occupied Shanghai, a young woman named Wong Chia Chi (Tei Wang) is recruited by the resistance to seduce the powerful Mr Yee (Tony Leung), a collaborator with the invaders. Over the course of several years, their relationship develops from mutual deception into a terrible sado-masochistic dependence.
Lust, Caution sees Ang Lee using the sedate formality of his earliest releases to tell a far more explosive story. Be warned: this is a film which proceeds at exactly its own pace, allotting as much screen time to the gossip of society ladies playing Mah-Jong as it does to a heart-stoppingly brutal killing. Much fuss has been made of the extremely frank sexual encounters between Leung and Tang, but the controversy is pointless: the sex is integral to the film. More than that even; the sex is the film. That title says it all really, Lust, Caution exists in the uneasy territory between orgasmic abandonment and suspicion. It's more like a chess game than a romance.
"A MESMERISING STUDY IN EMOTIONAL CRUELTY"
Leung and Tang, the old timer and the newcomer, both submerge themselves in the emotional muck with enormous courage, and Lee frames their helpless struggles with the cool detachment of a lepidopterist pinning a butterfly. This is a stern, steely film that requires considerable patience, but stick with it for long enough and you'll be rewarded with a mesmerising study in emotional cruelty.
I agree that the film is all about emotional cruelty. It's intens and hard to watch at certain times. But I disagree that it requires considerable patience. I knew it was a long movie and was worried a bit that my attention would drop at a certain point, but it didn't.
The cinematography is stunning. And despite the fact that as the review says, the sex scenes are the heart of the film, I think that the scene where the young woman sings for mr. Yee, really shows the intensity of what's going on between them, what the 'lust' is based on.
I think it's a must see movie.