Arthur Bishop's life is one of exact, excruciating isolation. He dubs himself "The Mechanic," but a more apt moniker might be The Impounder. He's an assassin, a foolproof assassin who knows how to send a message, how to make someone disappear or - and this is his specialty - how to make a kill look like death by natural causes.

Need to inflict a heart attack? A drowning? Arthur will get the job done.

As one might expect, he's a killer who lives in seclusion, unable to love or trust anyone - anyone except Harry (Donald Sutherland) that is, his boss and mentor. But when Harry's killed, Arthur adopts the orphaned son, Steve (Ben Foster), and introduces him to the family business. Together, they set out to get revenge against the man who killed Steve's dad.

It's all about pacing in "The Mechanic." The story moves so swiftly and the action unfolds so ferociously that the intensity becomes the thing.

From one mission to the next - missions that fly by, separated by only a couple minutes - Arthur proves himself practical, creative and innovative, able to overcome any unexpected surprise or detour. He takes out a dictator, eliminates a mole in his organization, kills a key member of another team of assassins and then sets out to find Harry's killer.

If most brooding thrillers of this sort focus on the preparations - the detailed hatchings of a plan - "The Mechanic" couldn't be less interested in the fine print. There's no preparation here, just execution - Arthur donning diving suits, parachutes and semi-automatic weapons whenever the occasion calls for it.

As Arthur's trainee, Steve is affable, but perhaps too quick of a study. We never quite see Arthur train his apprentice. Instead, Steve becomes a lethal weapon during his very first mission. He clearly knows a thing or two about this. All of which is well and good in providing the requisite thrills: Arthur and Steve improvise, people die, things blow up and the visceral thrills arrive in orderly fashion.

But where things fall short in "The Mechanic" is when it comes to suspense and texture. Arthur is so good at what he does, and Steve is such a perfect student that there's little doubt as to their invincibility - that no matter how complicated or how dangerous, Arthur will prevail.

Yes, director Simon West keeps things surging, but in maintaining that relentless momentum we lose any and all sense of down time or uncertainty - all that in-between stuff that can make a superhero seem more human. We ooh and aah over the fireworks in "The Mechanic," but when something's a given, it's a little harder to care about.

E-mail: snyderreviews@hotmail.com