Charlize Theron hilarious in grim comedy 'Young Adult'

CHARLIZE THERON knows a thing or two about playing predators - she won an Oscar for her role as a serial killer in "Monster."

And yet her murderess (in the movie's view) was a creature born of circumstance, of trauma. In "Young Adult," she plays a woman who in her own way is even worse.

Driven by bone-deep meanness, desperation, boredom, envy and alcoholism to pry a married man (Patrick Wilson) from his spouse and child and happy suburban home.

Did I mention it's a comedy?

It is, and Theron manages to be hilarious, a feat that has inspired new Oscar buzz for her turn in "Young Adult" as Mavis, an eroded high-school beauty who's now staring middle age and loneliness in the face.

She flinches, and impulsively flees the city for her dull hometown to retrieve the high-school dreamboat (Wilson) she fancies as her lifelong soul mate.

He's inconveniently married, but happily obtuse (a perfect role for the guileless Wilson), and he's also a guy, so unfortunate groin-based decisions are always possible.

"Young Adult" fashions this situation into a grim comedy, one that has unexpected echoes of classic movie scenarios (Barbara Stanwyck would have loved this role, stuck somewhere between "The Lady Eve" and "Double Indemnity").

And it throws in a wrinkle - Mavis finds a confessor in gnomish former classmate Matt (Patton Oswalt), who matches her bitterness and understands her disappointment. They become almost friends.

The cast is uniformly good - this is a hallmark of director Jason Reitman, who has an uncanny ability to put the right actor in the right role and to get the right performance. Even tiny roles stand out. The girl at the hotel counter should get some kind of miniature Oscar for her two-minute contribution.

They make "Young Adult" much more than it might have been on the page. There's something slightly phony and high-concept about Mavis' obsessive mission here. You don't really believe it, but you enjoy it anyway.

The screenplay is the w! ork of D iablo Cody, who wrote "Juno," which Reitman directed, and who gets a lot of blowback, probably because she brands herself and blogs and writes screenplays that are slightly glib.

Sometimes, though, her knack for the snappy line intersects with the truth. As when pregnant Juno's reproachful father says he didn't think she was "that kind of girl." Her reply - "I don't know what kind of girl I am" - gets to the essence of adolescence.

There's a subtle, riveting moment here of Mavis trying to tell her parents that she's an alcoholic, watching it sail over their heads. And there is a wordlessly effective sequence of Mavis girding for her manhunt, fixing her hair, makeup and clothes like a Spartan preparing for a Persian assault.

It's been said of Reitman that he's an unusual male director in that he actually likes women, and that's important here. Only by starting from a place of empathy can you make a train wreck like Mavis halfway interesting.

Other Reitman traits are on display - he's instinctively suspicious of adult characters who exist outside the gravitational pull of family (Aaron Eckhart's divorced father in "Thank You for Smoking," the never-married George Clooney in "Up in the Air") .

Theron is a female analogue to Clooney. She lives in a high-rise apartment photographed to look like solitary confinement, who talks of independence and success as though she's trying to convince herself of something.

She does not succeed, and in the final scenes makes a cathartic confession that shows her unvarnished, ugly interior.

It feels slightly unreal, and confirms the sense of artifice that dogs "Young Adult."

But doesn't ruin it. At every turn, "Young Adult" is buoyed by the fun of seeing Theron play one of the most ferocious man-eaters this side of "Shark Week."

When she's good, she's "Aeon Flux."

When she's bad, she's better.

Produced by Lianne Halfon, Russell Smith, Diablo Cody, Mason Novick, Jason Reitman, directed by Jason Reitman, written by! Diablo Cody, music by Rolfe Kent, distributed by Paramount Pictures.