With its combination of perverted romantic longing and political intrigue, Lust, Caution is essentially a more objective and detached variation on Hitchcock's Notorious. The Ingrid Bergman figure here is Wong Chia Chi (stunning newcomer Tang Wei), a young actress in Japanese-occupied China during WWII. Wong loves performing on stage so much that she willingly takes the art of inhabiting a character to a dangerous new level when she meets Kuang Yu Min, a politically active fellow drama student. Kuang cooks up a plot to assassinate Japanese collaborator Mr. Yee (Asian cinema legend Tony Leung) by using Wong to seduce him: she becomes Mrs. Mak, a sophisticated woman from Yee's upper crust world who will hopefully be able to put him in a vulnerable position. Yee is so cautious that it takes years for Wong to actually get him into bed, but once she does all his repressed urges toward her explode in a series of justly celebrated sex scenes. As time passes and political tensions rise, Wong and Yee's relationship becomes increasingly complicated and it becomes less and less clear where Wong ends and Mak begins.

Perhaps the most intriguing thing about Lust, Caution is the way that it totally inverts conventional dramaturgy; almost any other filmmaker but Lee would slowly reveal the heroine's true nature to the audience, but he goes the opposite direction, obscuring her motives and feelings more and more throughout the movie. Lee and his gifted lead actress totally embrace the idea of losing one's self in a role—Tang Wei not only loses herself in Wong Chia Chi, but Wong loses herself so completely in Mrs. Mak that her decisive actions late in the film are a total mystery to us (and maybe to Wong herself). For his part, Yee seems to be acting as well; his motivations are nearly as opaque as Wong's, and his behavior toward her in their sex scenes is so wildly erratic that it's impossible to tell how he really feels about her. At some points it appears as though Yee is genuinely in love, but at other moments he's so violent that such feelings seem unlikely—unless the abuse is what Wong wants, which is also floated as a possibility.

The world of Japanese-occupied Shanghai in which the bulk of the film takes place is so charged with political turmoil that everyone has been forced into playing a part, and this lends nearly every scene in the movie an intriguing sense of mystery. For some viewers the film might go too far in this sense, becoming so mysterious that it's impenetrable. The movie is over two-and-a-half hours long, and at the end of it we don't understand a whole lot more about the characters than we did when it began. Yet I think it's a mistake to judge Lust, Caution by the same standards as one of Lee's more conventional love stories like Brokeback Mountain or Sense and Sensibility, because he's up to something different (and, to my mind, superior) here. Lust, Caution is not about comprehending human behavior but about its endless sense of mystery, particularly in emotionally heightened times such as the period during which the film takes place. The graphic (for a mainstream movie by a major director, at least) sex scenes raise more questions about the characters than they answer, but they also provide a key to understanding the entire culture of WWII Shanghai, a world in which everyone is either oppressed or oppressor, and in which the political situation is so complex that the lines between the two are often blurred.