In Young Adult, Charlize Theron plays an ugly knockout. Her Mavis Gary isn’t a babe hiding behind glasses or bad makeup, à la her Oscar-winning turn Monster. Rather, she’s a 37-year-old writer who still wears Hello, Kitty! clothes and says things like “Gross.” She was voted Best Hair in high school, a time of her when she thinks she was “at her best,” which in reality meant making fun of a disabled kid and calling him “theater fag.”

Mavis went out with Buddy (Patrick Wilson) during those halcyon years, and they had sex and mixtapes and special songs. Hence, she’s not happy to get an email with a pic of Buddy’s newborn, a product of his happy marriage to someone who is not Mavis. We’re meant to be together, she believes. I’m going to go get him, she decides. So Mavis, living the itinerate life of a failing Y.A. author, packs her laptop and leaves Minneapolis for her podunk hometown.

Young Adult is directed by Jason Reitman (Juno) and penned by Diablo Cody (also Juno), and if you rolled your eyes at their previous collaboration’s twee, what-the-fuck verbosity, you should know the pair isn’t necesarilly cinematic kryptonite. There’s no “honest to blog” here; Young Adult’s script is mercifully underwritten. In fact, Cody now seems to have a reasonable grasp of how teens talk..

But while the dialogue is smooth, the story lacks. Girl-chases-boy may be a variation on a classic theme, and it is refreshing to see this kind of character portrayed as an anti-hero rather than a hopeless romantic—but it’s not enough. Mavis meets with Buddy a handful of times after returning home, dolling herself up and raising her hopes with his every nice word. Afterward, she turns to Matt (Patton Oswald), the classmate she once tormented, whom she runs into and decides to make her drinking buddy. (Mavis drinks a lot.) Soon, we start to feel like the friend who’s too polite to tell a torch-carrier to shut the hell up. So does the spinelessly nice Matt: “You need to move on!” he finally blurts after one of Mavis’ many brain-bleeding recaps. And that’s about all there is to the story—Mavis fantasizing, Mavis with Buddy, Mavis with Matt. It’s a short stretched to feature-length.

Theron, at least, keeps the film from being a total yawner; her character’s bitterness manifests in bedraggledness, even though Theron still looks, well, like Theron. (Sweatpants and a slouch help, but the actress is still gorgeous.) There’s a slice of lesson-learning here, which is hinted at throughout but more pointedly served at the end, when Mavis bemoans her fate to Matt’s sister (Collette Wolfe), who’s dazzled by the big-city writer. “Everyone wishes that they could be like you,” she tells a hungover Mavis. It seems to give her new resolve, but when Mavis gets back to Minneapolis, she’s still wearing sweats.