Not just to embody but to act the throes of passion, with every inch of flesh exposed - that's what first-time movie actress Tang Wei does to the hilt, and way beyond the hilt, in Lust, Caution, Ang Lee's otherwise ponderous tale of intrigue in Japanese-controlled Shanghai during the Second World War.

Tang Wei brings a terrible and awe-inspiring purity to an impure character: the key performer in a patriotic theater cell that becomes an assassination unit for the Chinese Resistance. At its best, the film presents a nightmare case of a performer getting lost in her role. The target of her seduction, a married collaborator and secret service chief played by Tony Leung, takes charge of their sexual relationship in a repulsive rape.

Lust, Caution (Focus) Starring Tony Leung, Tang Wei, Joan Chen. Directed by Ang Lee. Rated NC-17. Time 153 minutes.