Jonathan Levine, the writer/director of The Wackness, graduated from high school in 1994, the same year his film is set. Based on the writing here—smart and evocative when focusing on teenagers, histrionic and clichéd when the grownups get involved—he should wait until he's actually lived through middle age before he tries to write about it.

Dreamy jailbait Josh Peck plays Luke, a slack-jawed drug dealer who spends his summer days pushing an ice cream cart full of marijuana through Central Park. Like every teenager ever, he thinks he's depressed, so he trades weed for medical advice from psychiatrist Dr. Squires (Ben Kingsley). (Never mind that the mere sight of Kingsley these days is enough to induce depression in otherwise mentally sound individuals.) In case you were wondering about the quality of for-barter mental health care, a $30 bag of weed translates to diagnoses like, "You don't need medication, Luke—you just need to get laid."

And yet, Josh remains a friendless loner type—until he befriends Squires' fetching stepdaughter, Stephanie (Olivia Thirlby). Stephanie is way out of Josh's league, but he's smitten all the same, even as Stephanie's as careless with his feelings as only a pretty girl can be. Their flirtation is the best part of the film: The two young actors have a natural affinity, and a nose-bumping, sweaty-palmed chemistry that perfectly captures the reckless giddiness of a summer fling.

The chemistry between Josh and Squires is far less compelling (Ben Kingsley is in self-parody territory here, though he does get to make out with a hippied-out Mary-Kate Olsen), so it's to the film's detriment that a fair amount of the The Wackness hinges on the relationship between the two. While The Wackness succeeds when exploring the minefield of teenage relationships, it's muddled and overwrought when it comes to charting the land of grownups.