'Young Adult': Charlize Theron plays mean to perfection

When it's done right, as it is in "Young Adult," there is something absolutely mesmerizing about watching a train wreck unfold on screen. When the wreck in question is a narcissistic beauty played to scheming, sour, downward-spiraling perfection by Charlize Theron, cringing is definitely called for, but so is laughter.

In fact that's exactly the reaction director Jason Reitman and writer Diablo Cody are going for. Paired up for the first time since their 2007 knockout punch "Juno," the two ironists have switched sides in a sense. While "Juno" celebrated an acerbic, outsider pregnant teen, in "Young Adult" they are interested in the prom queen still pretty, still mean and now a decade into life on her own. It's not going well.

This is comedy extracted from pain start to finish, with its through-a-shot-glass-darkly story starting in Minneapolis or Mini-Apple, as her small hometown friends call it. Mavis (Theron) spends her days writing young adult novels, basically high school in-crowd pulp, and her nights making the club scene, binge-drinking, sleeping around and surprised to find happiness eluding her.

The self-absorbed stream of consciousness of a teenager that she needs for the books comes easily for her, which seems like a gift until you realize that is how she still thinks. The tim! e she sp ends writing in front of the computer, working through issues for her characters, also serves as a handy voice-over device to let us in on just how much growing up Mavis still has to do.

That journey begins in earnest when she heads back home to pick up things with her high school sweetheart, football star Buddy Slade (Patrick Wilson). That he's married and has just had a baby doesn't alter her resolve. But things take an unexpected turn when she encounters Matt Freehauf, the high school geek she'd forgotten about. Comedian Patton Oswalt ("King of Queens," "Big Fan") is exceptional playing a sarcastic devil's advocate, forever prodding Mavis toward her better self.

Their friction and their friendship, their brush with romance, is what gives the film its humor and its heart. "Young Adult" needs a lot of that to soften the outrage as Mavis sets about seducing Buddy, who looks as fresh-scrubbed and outdoorsy as if he just walked out of an L.L. Bean catalog. Elizabeth Reaser plays Beth, very likable as the new mom, the patient wife, a wannabe rocker who jams with a bunch of other new mothers. She represents a nice bit of smart tartness added to what is more typically a throw-away character. But Buddy and Beth are really just on the edge of the storm being whipped up by Mavis and Matt.

Theron and Oswalt turn out to be a terrific odd couple. Not easy because Cody's screenplay calls for, and Reitman demands, that they both reveal a great deal, and a great deal of what they reveal is exceedingly ugly. In Mavis, it is her unintentional drive to destroy everything and anyone who comes close and for this Theron uses her statuesque beauty as if! it is j ust something else in life to be squandered. Though Mavis is creating a different sort of mayhem than the murdering Aileen that earned Theron an Oscar for "Monster" in 2004, the actress has taken as much care in creating all of the character wrinkles the heaviness of an alcoholic getting started the morning after, the strands of hair she pulls when she can't drink away the nerves.

In contrast to Theron's beauty, Oswalt is required to play the beast specifically the gimp that no one who looks like Mavis should ever fall for. He's bitter about more than the fact that a brutal beating in high school left him nearly dead, the limp and the cane a constant reminder. That Oswalt is able to work the very raw deal Matt has been given to devastating and cynically and comically superb effect is a tribute to the extraordinary humorist/character actor he's become. He and Theron dance on the edge of arch from the first time they meet in a bar until the film's weirdly satisfying end.

Though this is very unlike "Juno," the film does share the distinctive voice of its writer. In Mavis, Cody is giving us another unexpected sort of female protagonist. Her great fondness for flaws makes it possible for us to empathize with the appalling, to savor the humor in the foibles. As a filmmaker, Reitman proves to be a very good counterbalance, the right mitigating factor for this particular mess.

In "Young Adult," the director continues to refine his imprint the light touch he brings to dark comedy, perhaps never more appealingly than in 2009's "Up in the Air," with George Clooney and Vera Farmiga caught in a bad romance. He is so completely at ease in the quirky, gritty worlds Cody creates, that it helps us deal with the discomfort.

Working with cinematographer Eric Steelberg, his frequent collaborator, Reitman allows just the right amount of grime into the people and places. The sports bar where so much of the action, and interaction, takes place, is a paean to middle-class malaise. There is a brashness of style that both Cody and Reitman embody almost demanding that we not only laugh at, but like the unlikable side of the human condition. That sort of bravado is fine if you've got the goods to back it up. In the cutting edginess of Theron and Oswalt, they definitely do.

betsy.sharkey@latimes.com