There's an appeal to the sniper's art -- the snick and snap of each hand-pulled bolt, the blue-steel poetry of it. Each cycle of the firing mechanism is as brief and constrained as a haiku, one that says the same thing over and over again: Die. Based on the novel by thriller writer and film critic Stephen Hunter (The Day Before Midnight, Pale Horse Coming), Shooter is an attempt to capture the essence of the sniper -- that most existential yet intimate of murders, where you shoot from a distance, killing one by one. Mark Wahlberg plays Bob Lee Swagger; when we meet Bob Lee, he's with Marine Force Recon, loaned out to shady suit-clad types in the name of some greater good. When Bob Lee's spotter Donnie (Lane Garrison) pulls a picture out of his fiancée out of his spotter's notebook, we sigh -- might as well be a boat called the Live Forever -- but we kind of accept that scenes like this are a necessary preamble in a certain kind of thriller, the overture before the curtain goes up.

Fade to black, and a title card tells us it is 36 months later, and Bob Lee is living in the woods with a tragic past, and an even more tragic ponytail. Men are looking for Bob Lee -- men with work to do. Led by Danny Glover, they explain that intercepted communiqués indicate someone will try to kill the President from a mile out with a single shot during scheduled appearances in our nation's capital, or Baltimore or Philadelphia. Not many people in the world could make that shot -- but Bob Lee could, so they want him to tell them where to look for the would-be assassin. He's an expert. He's a patriot. He's a patsy.

I'm not giving anything away here -- Shooter's big twist is in the trailer -- so the challenge is to make the how and why of the "good man betrayed" plot suspenseful. Shooter is directed by Antoine Fuqua -- who soared with Training Day and bored with King Arthur. Shooter has a down-to-the-bone kind of action filmmaking technique, and it also sneaks in a few sidelong looks at the apparatus of power, articulating a sneaky suspicion that the people in charge are often a bunch of crooks.

The film takes off with a burst of energy, with Bob Lee on the run, pursued and positioned as an enemy of the state. But Bob Lee don't die easy -- "The U.S. Government spent a lot of money teaching me how to stay alive, after they finished teaching me how to kill people ..." -- and he also manages to tell junior G-Man Nick Memphis (Michael Pena of The Shield and World Trade Center)that something is rotten in the state of Pennsylvania -- and possibly the District of Columbia.

Lee comes across as a down-home variation of Matt Damon's Jason Bourne -- a wire-tough guy, dangerous not just because of how he fights, but also because of how he thinks, and what he'll do to survive. Bob Lee enlists the aid of Donnie's fiancé Sarah (Kate Mara); Sarah is played as a 50-50 mix of "Stand by Your Man" American fortitude and inordinately tight and low-cut tops. Pena's Memphis -- reluctant, terrified and more than a bit mad at being shut down and set up by friend and enemy alike who want him to quit talking about crazy conspiracy theories -- is also brought into the game as a willing player on Bob Lee's side.

The fight for the right takes place all across America -- from the buildings of colonial Philadelphia to the fruited plains of Montana, both of which are full of convenient places to shoot people from.At one point, Bob Lee is driving a stolen car to get away, and Fuqua's camera glances at a space of sky between buildings, helicopters wheeling in place like hawks in a hot summer sky, slow and hungry. It's a nice image -- and in Shooter, just as in Training Day, a little power corrupts absolutely.

There's some nice supporting parts in Shooter -- or, at least, appealing actors in small roles. Elias Koteas is the creepy killing-chief of the bad guy's cabal; Ned Beatty plays the politico pulling the strings;Levon Helm is a conspiracy buff with a whisper-dry drawl and the right answers. Fuqua has a great eye for faces --- think back to some of the small-but-lively parts in Training Day -- and he casts some great ones here. He also pulls off making Wahlberg look like an action hero; previous Wahlberg films have turned his coolness into passivity, but here it's manifested as go-to-hell plain talk.

But, much like a round fired against a crosswind, Shooter goes a little off-target the further along it travels. Part of that is the structure of the story itself; Bob Lee's journey is a lot more engaging when he's running away from conspiracy as fast as he can, and loses a certain something when it switches in the final act to him walking towards murder with a hangman's methodical pace. At a certain point, the movie switches from being Three Days of the Condor -- adrenaline-riddled, wounded and hurtling -- and becomes more like a Steven Seagal film, as our hero sets out to kill a raft of supporting actors in an ascending order that roughly correlates to their paycheck.

There's also something a little skeevy about how Fenn spends a lot of the film being frightened or tortured in just her bra. The film also leans pretty heavily on a sort of fashionable cynicism --as so often in mainstream action film, the only thing that can save us from rogue elements of the government is, uh, nice elements of the government. Bob Lee is painted as both Gary Cooper and Clint Eastwood -- a man reluctant to kick ass, but once he starts, whoo boy, watch out. Shooter's a pretty, slick and pretty slick action flick; now and then, it may feel like a steroid-fed MacGyver episode, but when it's moving, it's alive.