"Infernal Affairs"

But Andy Lau's performance is so tightly controlled that it fits into that suit with room to spare. His character is almost shockingly cool -- we never see him ruffled, at least until close to the movie's end. Andy Lau never does anything obvious to telegraph the turmoil shivering beneath the surface of his character. Yet somehow, we never have any doubt that it's there.

Lau has the face of a grave elf. In scene after scene and shot after shot, we see him taking in information, processing it, filing it in the appropriate mental slot so he'll know how to use it later. But even though Detective Lau is an almost placidly still character (in fact, "Infernal Affairs" has very few shootouts and relatively little graphic violence; it builds all the excitement it needs through simple suspense), he gives off the sense of being constantly on the run. There's something distressingly unsettled about him -- it's as if the whole performance were inspired by the fierce but barely perceptible beating of an insect's wings.

But as terrific as Andy Lau is, "Infernal Affairs" is Leung's movie. Audiences with even a cursory familiarity with Hong Kong movies -- from John Woo's "Hard Boiled" and "A Bullet in the Head" to Wong Kar-Wai's "Chungking Express" and In the Mood for Love" to Zhang Yimou's justifiably exalted "Hero" -- will probably recognize Leung's face. Leung has been one of my favorite Hong Kong actors for years, and his performance here is one of the finest I've ever seen him give. His Chan has been working undercover for some 10 years. When he meets with Wong, who seems to be his only friend, he transmits the weight of his burden without exactly spelling it out. He's exhausted and despairing not because he lives a dual life, but because he lives only one: No one but Wong and, later, the police psychiatrist he flirts with in a few duskily muted romantic scenes, knows he's a cop. Everyone who knows him, knows him as a gangster, and he barely knows himself anymore.

Leung explains all of that with a few lines, but he tells us even more with his carriage (there are hints of physical exhaustion beneath its raffishness) and with the nearly drained-dry glimmering darkness of his eyes. As with Lau, all of Chan's despair is internal. He shields it from the world, as if it were a fragile creature that needed to be protected -- and it does, because it's the only thing that makes him feel human.

Leung's finest moment comes when Chan runs into an old girlfriend on the street, a woman he hasn't seen in six years. She has a little girl with her, her daughter. The two make awkward, emotionally charged chitchat for a few minutes. Chan asks the woman how old her little girl is; she tells him she's 5. After Chan walks away, the little girl tugs on her mother's sleeve and reminds her emphatically that she's 6. In other words, she's Chan's child.

That's the kind of moment that we might laugh at if we saw it, hamfistedly executed, in an American movie. But the scene is played with such weightless tenderness that it works. Hong Kong action films are often marked by a certain kind of sentimentality that "sophisticated" American audiences often find corny. And even "Infernal Affairs" has a few moments where string music swells beyond what we may feel comfortable with. Yet that music suits the tenor of the scene in which it's used -- it's one of the most deeply emotional moments in the picture, and it's fitting that it should be enveloped in an operatic bubble.

Andrew Lau and Mak keep most of "Infernal Affairs" so dry and taut that when they succumb to deep emotion, it actually means something. Chan and Detective Lau don't meet face-to-face until late in the movie, which means that through most of the story, their relationship is simply implied. Even so, it's always the center of the film, the unbreakable knot around which the whole thing revolves.

The themes of honor and loyalty, those old workhorses that pull many of the great gangster movies (Asian and American ones alike), are present here, but Lau and Mak skate around them lightly. The truer theme of "Infernal Affairs" is that brotherhood often has finite limits; a state of isolation is in some ways preferable -- at least you always know whom you're dealing with.

"Infernal Affairs" works as both a piece of entertainment and a solid genre exercise. But like the best of its kind, there's enough going on beneath the surface to stay with you. (Its fans will be happy to know that two sequels, one of them actually a prequel, have already been made.) "Infernal Affairs" also inspires us to ask ourselves what, aside from the country of origin, makes a picture distinctly "Asian" or "American"? There's no simple way to answer that question, but the simple truth is that "Infernal Affairs" gives us the best of both worlds.

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