No time to blink

WARNING: concentrate during the opening credit sequence or you'll watch the rest of this film clueless. First in black-and-white, then in colour, and then back again, a storyline is chucked at you with the speed of a confession made moments before an execution. The first three minutes of Infernal Affairs show just how an idealistic young cop came to work as an undercover gangster, and how his classmate became a gangster posing as an undercover cop. They are both thirtysomething and unhappy: they want to work normal jobs, ideally ones that d on't involve doing morse code during a drugs deal without anyone noticing.

So we whizz from trauma to trauma, one man arguing with his girlfriend, the other with his shrink; then on to shootouts, and chases in cinema multiplexes, with a weird guitar string being plucked on the soundtrack like the first bars of something by Jethro Tull on more Dexedrine.

Infernal Affairs thrilled everyone in Hong Kong, where it held the number-one slot over Christmas, outdoing The Lord of the Rings (take that, Gilthoniel). It stars Tony Leung (In The Mood For Love), who is magnificent as the slight, downbeat good guy with a Human League fringe and a woozy moustache (his character's pallor glows under the bristles).

But Infernal Affairs is much more than a Triad flick with an arty sheen: it is vulnerable and youthful, it comes at you all wide-eyed and full of news, darting excitedly about the place, and then occasionally collapsing for an exhausted cigarette break.

All the changes in rhythm and mood make it feel quite epic and longer than it is - in a good way. Expect a Hollywood remake pronto. Sadly it won't be half as nuts.

Infernal Affairs
Cert: 15