Jason Bourne (Matt Damon) can never stop moving. A rogue human weapon left for dead and without a memory in The Bourne Identity, he's driven by the twin motivations of keeping one step ahead of the government operatives who created him and learning the secret of his own past. He's both irresistible force and immovable object; you can almost feel the world around him shuddering as he exerts his will.

You might feel that sensation anyway even if Paul Greengrass weren't directing Bourne’s adventures, but it's certainly compounded by his presence. When he directed The Bourne Supremacy in 2004, Greengrass brought the hallmarks of his documentary film background to author Robert Ludlum's story: handheld cameras, and a nerve-wracking, jittery immediacy miles removed from the slick espionage thrillers of Cold Wars past. And while critics went nuts when Greengrass employed that style for the you-are-there gut punch of United 93, the notion of a genre franchise imbued with the same breathless urgency might seem a bit ... well, shaky.

With The Bourne Ultimatum, however, Greengrass manages to improve on a franchise that just keeps getting better. The action picks up in medias res from the end of Supremacy, with Bourne still on a quest for his history. When a British reporter (Paddy Considine) tracks down a source willing to spill the beans on the history of the Treadstone project that created him, Bourne sees an opportunity to get even closer to the truth. But forces within the American intelligence community -- including CIA Deputy Director Vosen (David Strathairn) -- will do anything and kill anyone to keep that truth hidden.

Joan Allen and Julia Stiles -- as Pam Landy and Nicky, respectively, CIA operatives sympathetic to Bourne -- return to the fold from previous Bourne films, but they're really all about Damon. The role demands someone whose intensity commands the screen even when he's not saying a word, and Damon has always played Bourne as though his life really did depend on it. The badass with a grudge may be an action movie staple, but few have played it with this kind of resigned, single-minded determination.

In many ways, though, the psychology of the central character matters less in this film than it has in any of the others. While we do see the flickers of memory that haunt Bourne, Ultimatum feels even more like a gritty Bond film with its emphasis on action set pieces and its globe-trotting locations. What Greengrass adds to the proceedings is an improbable combination of pure adrenaline and what-the-hell's-gonna-happen-next consequence. The two central chases are as riveting as anything you'll see on a screen this year. In the first, Bourne and the reporter try to make their way through London's Waterloo Station while CIA agents converge on them; in the other, on the streets and rooftops of Tangier, Morocco, Nicky tries to evade an assassin, who's trying to evade Bourne, who's trying to evade the police. See if you're just remembering to swallow or breathe at the end of both.

You're bound to see comments about Greengrass' direction that make reference to quivery hand-held shots that inspire a desire for Dramamine, or to the helter-skelter rhythms of his action editing. And yes, occasionally the fights and chases take on a chaotic quality that's far from crystal clear. Yet somehow it still works, because the director has created such a pervasive atmosphere of restlessness and tension that you find yourself in Bourne's skin.

If there is fault to be found, it's in the inevitable resolution of the Bourne mythology. It's here that Greengrass and his screenwriters -- including returning adapter Tony Gilroy -- chew over the narrative's morality most obviously, and indulge Albert Finney in yet another of his late-career performances where it seems like he's getting paid based on how long he can stretch out each syllable. The Bourne Ultimatum proves much more riveting when it's keeping up a propulsive pace, and allowing Greengrass to guide with a hand that's always steady -- even when his camera isn't.

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THE BOURNE ULTIMATUM

***1/2 (three and a half out of four stars)

Starring Matt Damon, Joan Allen, Julia Stiles

Directed by Paul Greengrass

Rated PG-13