As the on-the-run amnesiac hero of The Bourne Identity, Matt Damon, playing an assassin without a cause, gets to show off some very deftly timed martial-arts moves, flipping his limbs around with the slashy percussive precision of ninja nunchakus. In his first bona fide action-demigod role, Damon also speaks fluent French and German, and he escapes, brick by brick, down a wall in a scene that's photographed from angles steep enough to give Spider-Man vertigo. When he catwalks into a room, he has a way of sizing up the place for potential killers as if his senses could lead him in 12 directions at once.
Some of this stuff is enjoyable in a flashy if familiar way. Bourne, who has been injured in a mysterious fracas (the movie opens with him being plucked unconscious out of the Mediterranean Sea by the crew of an Italian fishing vessel), is some sort of black-ops shadow agent on assignment in Europe, but he has lost touch with any memory of who he is or how he got there. He still has his espionage instincts, though: Without even thinking about it, he knows how to fight, how to hide, how to slither out of danger. Damon's whole persona -- nimble yet terse, quick on the draw, always aggressively centered -- is that of someone who uses his wits and his gyroscopic cool to master every situation. In his 20/20 radar way, the actor exudes so much authoritative savvy that he makes Jason Bourne seem magically at ease in his nonpersonhood.
As ''The Bourne Identity'' goes along, the hero's survival hinges on his ability to unravel the enigma of his identity, but Damon, despite a few moments of who-in-God's-name-am-I desperation, seems pretty much the same butt-kicking golden boy of the information age all the way through. He's the anti-Ripley. (No nervous tremors here.) The movie, which is adapted from one of Robert Ludlum's convoluted pulp novels, is a conventional chase thriller posing as a psychological-puzzle spy mystery. It has a few whispers of intrigue, but at the heart of ''The Bourne Identity'' lies a dispiriting paradox: The more that Jason Bourne learns about himself, the less arresting he seems.
Damon is on record as saying, in essence, that he didn't want to bust his summer-action cherry by making just any old thriller, and it seems safe to guess that the film's director, Doug Liman, was driven by a similar sentiment. Liman's previous two features, ''Swingers'' (1996) and ''Go'' (1999), are among the most buoyant and free-spirited of the last decade's indie comedies; he brought them a dizzyingly funny and exacting feel for how the generation that came of age in the '90s turned ironic role-surfing into a new form of romance. Liman and Damon, with his whiz kid's avid brashness, would seem to be a perfect match, but ''The Bourne Identity,'' which plays like John Le Carré with a couple of burnt-out cylinders, is far more routine than they apparently think it is. It's fleetly staged, yet mechanical in all the ways that ''Memento,'' that swizzle-cut noir of moment-to-moment identity retrieval, was not.
At first, we're held by Bourne's dilemma. With nothing to go on but a Swiss bank account number implanted in his skin, he retrieves the safety deposit box's contents and discovers a wad of fake passports. It seems that he's Jason Bourne and a great many other people as well. Or is the man of a dozen international personalities really ''nobody'' at all? The film cuts back and forth between Bourne and the ruthless scramblings at CIA headquarters, where a furrowed supervisor (Chris Cooper) is using every surveillance device within his power to track Bourne down -- and possibly kill him. Unfortunately, the CIA scenes allow us to grasp from virtually the outset who, in essence, Jason Bourne is. He's an underground cipher out of a cliché-packed spy yarn, and that's about all. Nothing that Liman and Damon do can shake the luggishness out of Ludlum.
If Bourne himself had been shocked, or even appalled, by the hidden reality of his existence, then the movie might have generated some more tension. But ''The Bourne Identity'' has a sullen roteness that all of Liman's supple handheld staging can't disguise. Bourne offers $20,000 to Marie, a young woman he glimpses in the American embassy, if she'll drive him from Zurich to Paris. Franka Potente, the German star of ''Run Lola Run,'' makes a winning Obligatory Love Interest (she's like a more flirtatious Lili Taylor), but there's no getting around the facile -- and rather farfetched -- nature of the relationship. It's a measure of the film's mechanistic anonymity that even as elegant a predator as Clive Owen, cast as a CIA assassin in glasses and a dorkish trench coat, leaves very little impression. Ludlum's novel was published in 1980, and it bears the mark of an era when the CIA could still appear all-powerful and also all-sinister: the good guys acting as amorally as the bad guys. But ''The Bourne Identity'' now feels, if anything, even more dated than the Cold War nostalgia of ''The Sum of All Fears.'' The movie wants us to look at these government-sanctioned superkillers and say, How ominous. Instead, a lot of viewers may now think, As if, or even, If only.More Action/Adventure Movies