Lust, Caution director Ang Lee's movies often deal with repressed desires, confined by some kind of external, uncontrollable circumstance. It's a situation that's easy to identify with, and Lee has always been adept at communicating the depth of the desires. Much of the time, that's based on understanding that the protagonists know where their hearts truly lie. But what happens when even the protagonist is not sure?

Lust, Caution happily takes the director a little further out of his comfort zone, but the wobbliness shows. This time, the situation in which the heroine finds herself is one she volunteered for. Not only that, she has to feel her way through it, all the while blurring her identity along the way. As a result, the character feels a bit distant -- we can never really know her mind, and her motives remain ambiguous. They may be unclear, even to her.

The tale is based on Eileen Chang's short story, set during the Japanese occupation of China in the 1940's. A student named Wong Chia Chi (Tang Wei) finds herself caught up with a group of young Chinese idealists, a group of would-be actors, determined to take action against those Chinese officials who have agreed to collaborate with the Japanese government. They target a certain Mr. Yee (Tony Leung Chiu-Wai) in Hong Kong, where Wong has agreed to infiltrate Mrs. Yee's (Joan Chen) circle of mahjong-playing friends in the guise of "Mrs. Mak." Their goal is nothing short of creating a chance to assassinate Mr. Yee.

But the politics of the situation begin to settle for just being the backdrop, as the story concentrates on what Wong goes through as she plays her part. She doesn't seem fully convinced of the politics to begin with -- the group's leader, Kuang Yu Min (Wang Leehom) is the zealous patriot -- so she's going along either to find a place to fit in or because there's something about the danger that she likes. We're never really sure. As the story progresses and the location eventually shifts to Shanghai, Wong/Mrs. Mak finds herself even deeper in the role.

Mr. Yee, paranoid about just the kind of operation Wong is involved in, allows himself to be drawn to her. He may be playing a part as well -- he's a Japanese collaborator but never seems particularly proud of it. His interactions with Mrs. Mak do arrive at the physically graphic in bed, and is it only here that both participants feel true, unrestricted feelings? Again, because both characters are so cautious, we never quite find that emotional hook to latch on to. What we see is that Wong has put herself into a very deadly situation, and she looks lost about what she should be thinking, so she follows the only thing she knows is real, even if doing so could lead her to a dead end.

This sort of ambiguity is usually received well by me, but this time the delivery feels a bit stuffy. As a period drama, Lust, Caution appears done up to look quite nice, but overall the piece takes the mood of its main characters -- careful, trepidatious, unknowable. The fulfillment of lust should feel like a release, but instead it feels contained, since Wong seems to be always conscious of the predicament she's in.

I'm a bit sad to report that, although I think it's good, this may be the first Lee movie I've watched that didn't hit a home run (or near-home run) with me. I'm quite certain Lee got the mood he wanted for the movie, and Tang plays her part with amazing control for her feature film debut; that is, the character is portrayed successfully. But I'm not certain Wong/Mrs. Mak, with her youthful uncertainty and her plain fear uncountered by any evidence of plain ecstasy, is someone we can easily feel fascination or an affinity for.

(Released by Focus Features and rated "NC-17" for some explicit sexuality.)

Review also posted at www.windowtothemovies.com.