Billy is a 15-year-old boy living in rural Maine. He’s also THAT KID you went to high school with—you know, the one who sports a rattail and sits in the corner of the lunchroom snarfing chips with his mouth open. He’s the one who ventures beyond the conventional borders of dorkiness into the lonely desert of hopeless weirdness. Jennifer Venditti follows him there. Her documentary starts with a shot of Billy cracking up as he shows the camera his uvula: “It’s that dangly thing at the back of the mouth,” he says helpfully. Billy then goes on to provide a succinct and hilarious narrative of his life and times. He loves Kiss and karate and has “a big interest in girls.” Slowly, darker revelations emerge. His stepfather is chronically absent. His biological father smoked crack and abused his mother, who was told by doctors that Billy would have to be institutionalized. That turned out not to be true, but still, nobody knows quite what Billy “is.” He’s relegated to “special” classes, but has a GRE-worthy vocabulary and a wise outlook on life. Like an adolescent Don Quixote, he rides (his bike) through town, looking for bullies to beat up and exposing a chivalrous streak. (“Unfortunately, I’ve never been the savior of a damsel,” he laments.) Structurally and thematically, Billy the Kid is utterly original. As for Billy, the kid? It doesn’t take a prophet to see trouble in his future. But there’s also no doubt that someday he will save someone for real.