The twentysomething youth scene we see in this brilliant, chilling film is a moral black hole festering in the sun-baked suburbs of Southern California. Its inhabitants are well-to-do white stoner kids, stumbling through their wasted days in a haze of pot smoke, meth buzz and gangsta rap -- the music that makes them feel like for-real street thugs as they run their well-organized drug deals and party nonstop on the proceeds. They talk in an assaultive lingo of the bitch-ho variety, and at first they seem like utter scum -- until we meet the emotional-absentee parents who've cut them adrift. The movie is based closely on a terrible true story, and it holds nothing back. The cast -- a roll call of some of the most talented young actors in the business right now, including Emile Hirsch, Ben Foster and, yes, Justin Timberlake -- brings the characters to life unforgettably. The picture is rated "R" for good reason. Unfortunately, that rating means that some of the people who might find it most horrifically edifying won't be able to see it. (Well, maybe.)

On August 6, 2000, a 15-year-old boy named Nick Markowitz was abducted off a San Fernando Valley street -- pushed into a van after some light beating and kicking -- by a young marijuana mogul, Jesse James Hollywood (his real name), and some associates. At the age of 20, Hollywood was already living in a $200,000 house (for which he'd made the down payment in cash) and driving a Mercedes. He ran a no-nonsense business, and when one of his dealers, a childhood friend named Ben Markowitz, stiffed him for $1,200, Hollywood decided to take drastic action to force repayment. Kidnapping Ben's half-brother Nick was a whim, an opportunity that suddenly presented itself.

Nick was a personable kid who admired his brother and his drug-world associates as definitively cool guys. His captors immediately took a liking to him, and for two days they fed him drinks, got him high and turned him on to the hot chicks who thronged their scene. They planned to free their "stolen boy," as they jokingly called him, as soon as his brother came up with the money he owed. But he didn't. And when Hollywood learned from his lawyer that the penalty for kidnapping was life in prison, he ordered his dimwit street soldiers to kill their captive. They marched Nick into a national park, duct-taped his hands, hit him in the head with a shovel and sprayed him with a TEC-9 machine pistol. His body was discovered four days later.

Over the course of his brief captivity, Nick Markowitz had been paraded around in front of what turned out to be 38 witnesses. The four members of the kill-squad were quickly apprehended, eventually tried, and given sentences ranging from eight years in a juvenile lockup to the death penalty. Hollywood, however, who had not been present at the scene of the murder, had disappeared, and he immediately became the youngest fugitive on the FBI's Most Wanted list, where he remained for the next four and a half years.

Ron Zonen, the Santa Barbara deputy DA in charge of the case, was determined to find Hollywood, and when director Nick Cassavetes turned up researching the story for this movie, Zonen turned over to him all the confidential police files on the investigation, hoping the film might flush out the fugitive pot kingpin. "Alpha Dog" was already shot and wrapped by March of 2005, when Hollywood was finally found and arrested -- in a small beach town in Brazil, where he'd allegedly been living on a monthly stipend from his shadowy father -- and returned to the States. His attorneys managed to get Zonen taken off the case for unethical behavior, but ultimately couldn't prevent the release of the movie, which, despite its name changes and some hasty post-production fictional embroidery, clearly compromises Hollywood's ability to defend himself. Legal wrangling in the case continues.

In "Alpha Dog," Hirsch plays Johnny Truelove -- the Jesse James Hollywood character -- as a pot-fogged but wily junior drug-trade executive, a soft-spoken operator who is nevertheless not to be messed with. Timberlake is Frankie Ballenbacher, one of his top lieutenants, a good-hearted guy who's so high all the time that he's easily manipulated into doing just about anything. Anton Yelchin plays Zack Mazursky, the "stolen boy" -- a smart but credulous teen whose feckless parents (David Thornton and Sharon Stone) have left him with no one else to look up to but his dangerous, meth-addled half-brother, Jake. And in that role, Ben Foster, bristling with tattoos and vibrating with a wild, drug-wired energy, gives the movie's most electrifying performance.

Working with the veteran French cinematographer Robert Fraisse ("Hotel Rwanda"), Cassavetes, who also scripted the movie, has constructed scenes of indelible narrative power and an eerie pictorial beauty. The sequence in which Zack is seduced in a glowing blue swimming pool by two young party girls (they're turned on by his virginal innocence, a quality that, despite their own tender ages, they left behind long ago) has an extraordinary emotional resonance. And when Frankie keeps offering Zack opportunities to escape -- to climb on a bus and return home -- and Zack keeps turning him down (he thinks his abduction is just a game that'll soon be over -- which it will), we feel a slow-building despair about the awful fate bearing down on him that's finally overwhelming. The execution scene at the end, played out on a rocky, moonlit mountaintop under a sky overloaded with stars, is one of the most horrible and heart-rending sequences in recent films.

The big showbiz news here, of course, is Justin Timberlake -- even if he weren't already established as a major pop star, his career as an unusually skilled character actor would be assured. He plays the amoral Frankie with an easy, befuddled charm that's irresistible. But there are a dozen other fine performances in the movie, some of them quite small. Ben Foster owns every scene he's in: He manages to invest his viciously unstable character with a violent, off-the-wall humor that's a marvel to watch. But in a scene in his squalid apartment, surrounded by empty beer bottles and vintage Nazi memorabilia, Heather Wahlquist does a vivid turn as his slutty girlfriend, signaling a witty, vestigial intelligence with the schoolgirl glasses she keeps adjusting on her nose. And Bruce Willis discards his smirky charm to bring out the full sleaziness of Johnny's scumbag father, who loves to get wasted with the kids, and who fronts the money to finance some of his son's drug deals.

There are in fact no bad performances in this picture. The events depicted are often ugly and sometimes repulsive, but Cassavetes never flinches from depicting them fully. It's a very dark movie, frequently reminiscent of such teens-gone-wild Larry Clark films as "Kids" and "Bully." Sitting through it is not an entirely pleasant experience -- how could it be? -- but you walk out of it knowing you've seen something disturbingly new. And maybe wanting to see it again.

Check out everything we've got on "Alpha Dog".

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