Immature teen-fiction author Mavis (Charlize Theron) returns to her Minnesota home town, intent on luring away her now happily married high-school boyfriend (Patrick Wilson), in this caustic and self-consciously quirky satire that reunites director Jason Reitman with Juno writer Diablo Cody. There are daringly no redeeming qualities to Theron's odious former prom queen. Instead, razor-sharp putdowns and Theron's fearlessly unrestrained performance provide car-crash entertainment as, back on her old stomping ground, the delusional Mavis's barely hidden neuroses come spewing out in a barrage of amusingly monstrous banter. If this unrepentant nastiness gives the narrative bite, its heart is provided by Mavis's crippled ex-classmate and sardonic voice-of-reason Matt (a scene-stealing Patton Oswalt). In showing Mavis a warmth and kindness she really doesn't deserve, the heroic misfit personifies the story's underlying moral message and adds emotional depth to an otherwise slight affair.