Young Adult loves to hate its childish heroine

Charlize Theron gives hilarious performance as a former high school Heather

Charlize Theron won a Best Actress Oscar for Monster, her 2003 portrayal of serial killer Aileen Wuornos. In Diablo Cody's dark comedy Young Adult, Theron's character doesn't kill people, but she is monstrous in her own way.

Theron plays 37-year-old Mavis Gary, who joylessly writes installments of a Young Adult book series called Waverly Prep. Mavis is one of those people who peaked as a popular high school teenager, but never realized that the real world operates by different rules. She lives alone in Minneapolis where she neglects her dog, has dreary affairs, and passes out facedown every night. But hey, at least she's not stuck in her hometown of Mercury, Minn.

An email photo of her high school sweetheart Buddy's (Patrick Wilson) new baby jolts Mavis out of her rut. Mavis, reasoning that she and Buddy are meant to be together, returns to Mercury to steal Buddy from his happy family. The film takes wicked glee in its anti-heroine's nasty narcissism.

Young Adult offers a kind of class reunion of Jason Reitman and Cody, the director and writer, respectively, of the teen pregnancy comedy Juno. (Cody won a Best Original Screenplay Oscar for the film.) If you still shudder at the memory of Cody's too-clever dialogue, rest assured that Young Adult plays more like one of Alexander Payne's caustic but credible satires of Middle America like Election. Mavis' hometown turns out to be a wasteland of fast food joints and chain superstores, but her old acquaintances prove good-hearted despite their lack of sophistication.

Reitman presents deliberately slick montages of Mavis getting pedicures and makeup to ensnare Buddy. As Buddy, Wilson's cheerful, sleep-deprived new dad scarcely seems like the Prince Charming Mavis remembers, although he turns out to be more insightful than he lets on. She refuses to believe that Buddy genuinely loves his baby and wife (Elizabeth Reaser), a compact brunette who teaches special needs kids, plays drums in a band of fellow moms, and generally makes a warm, huggable contrast to Mavis's icy ambition.

As Mavis contemplates extreme measures to win Buddy, she spends time with former classmate Matt (Patton Oswalt). A lonely loser who walks with a cane, Matt turns out to be a voice of reason with some quirky hobbies, like distilling aged bourbon in his garage. Mavis barely notices his virtues, but spends time with him mostly because she needs a social inferior so she can feel better about herself.

Of course, Theron is stunningly beautiful all dolled up, but she revels in the slovenly scenes that reinforce Mavis' childish self-absorption. She starts each morning by suckling at a 2-liter bottle of Diet Coke like a baby goat, and tends to trudge along with a toddler's graceless shuffle when hungover. As Mavis writes the latest Waverly Prep novel, her descriptions of the book's Little-Miss-Perfect protagonist serve as a surrogate for the author: "Kendall Strickland was going to think about herself for a change!" she writes, even though Mavis never thinks about anyone else. Of all of this year's portrayals of women behaving badly, Mavis deserves to be crowned Homecoming Queen, and maybe get a bucket of pig blood to go with it.