Timberlake’s performance as Frankie is a standout, emotionally complex and believably street-tough. But Zack eventually becomes a liability rather than an asset as the spur-of-the-moment kidnapping drags on for days with no resolution in sight. There’s a certain tenderness in the almost brotherly bond that develops between them. Frankie takes care of him, brings him along to his dad’s house in Palm Springs, where there’s a swimming pool and a place to sleep. He becomes friends with Frankie and with Frankie’s associate Keith (Chris Marquette). Zack, for his part, a naive and inexperienced lad, is having a great time going from party to party, being hit on by girls and offered drinks. Johnny doesn’t want him either, so Frankie is stuck with him. Problem is, Jake is MIA, leaving Frankie with this hostage he doesn’t really want. They have no reason to hurt him, just hang onto him until Jake comes through with the money. Unable to find Jake, Johnny’s guys, led by a thug named Frankie (Timberlake), do the next best thing: They snatch young Zack up off the street and more or less hold him prisoner. This debt infuriates Johnny, and a feud ensues. His father (David Thornton) and spiteful stepmother (Sharon Stone) won’t give it to him, and his 15-year-old half-brother Zack (Anton Yelchin) - who looks up to Jake like a demigod - doesn’t have it. Meanwhile, we meet Jake Mazursky (Ben Foster), a profoundly unstable meth-head who owes Johnny a chunk of cash that he can’t seem to come up with at the moment. One boy (Shawn Hatosy) is cleaning Johnny’s garage just because he was told to. They’re abusive, sexist kids who cruise from one drug-fueled party to another, always ready to follow orders from Johnny. His fellow teens, meanwhile, emulate the gangsters they see in rap videos. Johnny has a “Scarface” poster on his wall, and he emulates that character in his business decisions. And so their leader is another kid, a teenage drug lord - he can’t be more than 17 - named Johnny Truelove (Emile Hirsch). To the extent that they have parents, the parents are ineffectual.
The characters are kids with no ethics, no roots and no direction. The film is a fictionalized account of a true story, set in Claremont, Calif., in 1999. (All due respect to fans of “The Notebook.”) What happened to Cassavetes and Timberlake to make them go this direction, I don’t know, but I’m glad they did. Yet here it is, a gritty urban crime drama involving teenagers, guns, drugs and sex, all sharply acted, well-directed and astutely put together, with Timberlake’s performance as one of its greatest attributes. This thing has “mediocrity” written all over it. Furthermore, it features Justin Timberlake in a leading dramatic role. It was written and directed by Nick Cassavetes, whose previous output ( “John Q” and “The Notebook,” particularly) has been proficient but strictly by-the-numbers. “Alpha Dog” is in some ways a revelatory film.