If ''Lucky Number Slevin" was as good as it is clever, we'd be talking four stars here. A hyperactive, style-crazed crime caper of revenge and mistaken identity, it operates in a slick little playground all its own. When the movie's over, you know you've seen something, but you may wonder what or, more important, why. It's like being fleeced by a con artist who's more interested in the scam than the score.
The con artist in question is Paul McGuigan, the Scottish director of ''Gangster No. 1" and the stupid but hugely entertaining ''Wicker Park." He's part of the gang of new British cutthroats that includes Guy Ritchie (''Lock, Stock and Two Smoking Barrels") and Matthew Vaughn (''Layer Cake"), filmmakers who deliver the old ultra-violence with Cool Britannia flair. Their movies can be nasty fun -- if almost entirely derivative of ''Pulp Fiction" -- but they're always in danger of disappearing up their own hindquarters. ''Lucky Number Slevin" is merely the first to go the distance.
After an opening sequence that dispatches a handful of thugs in glitteringly brutal fashion, the film settles down to tell the story of a young man named Slevin (Josh Hartnett) who arrives in New York to stay with a friend. The friend is missing, he owes a lot of money, and the gangsters who show up at the apartment assume Slevin's the man they're looking for. They drag him to a conference with the Boss (Morgan Freeman), who lives in baronial penthouse splendor directly across from his criminal rival the Rabbi (Ben Kingsley).
Wow. So far, so good: Sir Ben and God in the same movie. Hartnett still looks like he was formed from the leftover parts of Tommy Lee Jones, but he tries to hold his weight in this company. As Slevin pits the two kingpins against each other, he puts up with abuse like a good noir hero -- he has his nose broken twice and spends the first third of the movie wearing a bath towel -- and Jason Smilovic's script lets him shoot off dry zingers in all directions. ''I bet it was that mouth that got you that nose," says the Boss. True enough, but it's Hartnett's barely disguised smugness that makes the audience want to smack him after a while.
The most original thing about ''Lucky Number Slevin" is that it lets Lucy Liu play a screwball heroine. About time, too. She's Lindsey, the free spirit next door, and her scenes with Hartnett are adorably overwritten arabesques of smart-girl banter. Her dialogue is too, too arch -- ''If you're still alive after I get back from work, wanna go have dinner?" -- but the flicker of honest mischief in Liu's eyes is the only thing here that doesn't seem unbearably pleased with itself.
McGuigan piles on the absurdities and look-at-me filmmaking: Orthodox gangsters, triple-split screens, flashbacks and flash-forwards and flash-sidewayses. He and Smilovic indulge their love of old movies past the breaking point, and when Slevin and the Rabbi discourse on Eva Marie Saint in ''North by Northwest," the scene could be subtitled ''Inspired by the Collected Works of Quentin Tarantino." (That said, Kingsley makes the Rabbi's Talmudic ditherings extremely funny, especially in the early scenes.) Bruce Willis and Stanley Tucci turn up in crucial supporting roles -- one as a hit man, the other as a Fed -- but even the plot twists regarding their characters feel overly familiar. If you put stale ingredients in a blender, the results don't taste any fresher.
Some will mistake the studied breeziness of ''Lucky Number Slevin" for art or entertainment, or they just won't care -- McGuigan plays to the new callousness well. (So does Tarantino, but his sheer love of making movies pulls him through.) It's telling, though, that the slick, computer-enhanced production design never suggests the real world but rather the confines of a video game. ''Slevin" mashes our buttons with verve, but the game's over long before the movie is.
Ty Burr can be reached at email@example.com.