Directed by Tony Scott. Starring Keira Knightley, Mickey Rourke, and Christopher Walken. Rated 18A. For showtimes, please see page 80

Domino opens with the three words A true story and then, like an afterthought or a punch line, sort of appears on-screen. And so begins an apt film for our TV-fixated times, when-whether it's Survivor, Jerry Springer, or Bounty Hunter-no one knows or cares where reality stops and fiction begins.

Director Tony Scott ratchets up his usual tweaked-out visuals to tell the story of the late Domino Harvey, a Beverly Hills rich kid-turned-bounty hunter. But neither Scott nor screenwriter Richard Kelly seem at all interested in uncovering who she really was. Rather, the shotgun-toting, neck-tattooed thrill seeker becomes an excuse for exploring everything from trash TV to America's health-care crisis. The result is never as smart or as hip as the filmmaker wants it to be.

When we first meet Domino (Keira Knightley), she's got blood caked on her face and is under interrogation by a criminal psychologist (Lucy Liu). Flash back to the nasty bit of mayhem that she's being questioned about: a tense desert standoff involving a blood-spattered Winnebago, millions of dollars, and a one-armed man. Rewind again, and the rest of the movie frenetically traces the events that led Domino to that ugly scene, starting with her childhood as a British boarding-school student, the daughter of a famous actor dad (Laurence Harvey) and a gold-digging mother (played by Jacqueline Bisset). Whether she's modelling on European runways or joining a university sorority, Domino never fits in-until she discovers there's a job chasing bail jumpers that will feed her taste for danger.

She hooks up with bounty hunter Ed (Mickey Rourke, in a role he was born to play) and his team, Venezuelan ex-con Choco (Edgar Ramirez) and Afghan bomb nut (Riz Abbasi). They form a kind of gunslinging surrogate family until their bail bondsman (Delroy Lindo) leads them into a royally botched bust that involves Las Vegas casino owners and the Mafia.

Proving movies don't have to be deep to entertain, Domino hurtles along like that blood-soaked Winnebago. En route, just as he did in 1993's True Romance, Scott introduces us to some brilliantly warped bit parts. Christopher Walken is just one of the guilty pleasures, revelling in his role as a reality-TV producer who, as his assistant puts it, "has the attention span of a ferret on crystal meth".

But even as Scott creates all these colourful side characters, he shortchanges the main one. Knightley brings credible bad-ass energy to her role, but she's reduced to a fetishized, Maxim-ized assassin, even lap-dancing her way out of one gangland confrontation. Obviously, Domino confounded Scott himself, a director who supposedly regarded her as a daughter when she drowned in her tub, at 35, due to a drug overdose earlier this year. When the buzz of his movie's adrenaline rush wears off, you're left wondering why he didn't work up more empathy for her. Domino, and her self-destructive impulses, remains as much of a mystery as before he made the film.