Directed by Nick Cassavetes

Rated: R

(three stars)

Coming of age stories are typically an exercise in sentimentality. They offer an airbrushed view of the first fumbling act of liberation into adulthood. But in truth the right of passage is a series of collisions-big and small-between fantasy and reality, between unformed judgment and unforgiving consequence.

In his latest movie, "Alpha Dog", director Nick Cassavetes adapts the story of a suburban teenager who made the FBI's most wanted list-and shattered the lives of those around him-with a stunningly senseless act of violence.

The Film opens with a montage of home movies of young children backed by a cover of "Somewhere Over the Rainbow". It's an ode to the journey out of childhood innocence and a sweet counterpoint to our introduction to Johnny Truelove (Emile Hirsch) and his friends. This gang of teenage pseudo-toughs is still playing, but now at being the kind of hard men that suburbia doesn't create. They posture and bully each other, particularly their weakest member, Elvis (Shawn Hatosy) who Johnny seems to take pleasure in humiliating.

Johnny has built a tidy little business and a great deal of social status in the local teen culture dealing drugs he gets from his mob-connected dad, Sonny (Bruce Willis).

The fly in Johnny's ointment is Jake Mazursky (Ben Foster), who starts racking up bad debt in his drug buys. Johnny's problem has less to do with cash flow than with his image as a tough guy. He puts pressure on Jake but, unlike Elvis, Jake leans back and the two get involved in a series of bluffs that Johnny can't back up.

Johnny's search for leverage ends unexpectedly as he and his crew discover Jake's fifteen year old brother Zack (Anton Yelchin) walking down the road. They hustle Zack into their van but once they have a hostage on their hands they run out of ideas. Johnny dumps Zack in the care of Frankie (Justin Timberlake) while he heads off to confront Jake.

Zack latches onto Frankie, tagging along through an unsupervised paradise of parties and hanging out.

Cassavetes' movies usually display a genius for casting and the teenage world of "Alpha Dog" is populated with interesting performances by underrated actors. Chris Marquette (Adam in "Joan of Arcadia") is spot on as an affluent dope-smoking waif and Amanda Seyfried (the vacant Karen of "mean girls") deserves more screen time as Zack's new-found love interest, Julie.

Best supporting role honors, however, should go to Harry Dean Stanton as Cosmo Gadabeeti, Sonny Truelove's sidekick. Cassavetes describes his film presence as "a walking fog" and Stanton does add a welcome layer of atmosphere to every film he's in. Willis does a fine job as Sonny but somehow his pairing with Stanton produces a whole that is greater than the sum of its parts.

But Cassavetes masterstroke of casting is (much to my surprise) Justin Timberlake. Timberlake, whose closest association with crime has to do with a wardrobe malfunction, shows up in this movie with a collection of tattoos that would make a suitable fashion statement on Cell Block D. In the early scenes it just seems wrong and Timberlake's presence a misstep. But the story is going to need him before it's through and Timberlake delivers.

Films that try to retrace an actual event tend to get tangled up in the untidy complexity of reality. They end up canvassing a lot of territory while tragedy yearns to stay close its tipping point.

When Johnny begins panic about the consequences of his actions "Alpha Dog" narrows down to a story of three people. Elvis, who will do anything to disprove his wounded self-image, agrees to silence Zack, who in turn is so enamored with Frankie and Julie that he's indifferent to any opportunity to escape. It's left up to Frankie to protect him. Timberlake delivers a selfless performance, capturing a perfect blend of decency and weakness. Timberlake's Frankie keeps the story balanced on a knife edge between redemption and tragedy right up until its gut-punch of a climax.