Teeth is a horror comedy, and like any entry in the genre, it requires a certain suspension of disbelief. So I’m perfectly willing to accept that growing up next to a nuclear reactor might cause a girl to develop interlocking incisors in her vagina. (Things happen.) But I’m a little more skeptical that a year and a half of sexual abstinence will turn a teenage boy into a rapist. Still, here are Dawn (Jess Weixler) and Tobey (Hale Appleman) bending their chastity vows in a woodland vale—and here’s Tobey suddenly not taking no for an answer, and here’s a sound like somebody biting into an apple, and Tobey’s clutching his groin like he’s just had an encounter with Lorena Bobbitt, or the world’s clumsiest mohel. You see what happens when you deny your healthy natural urges, Christian kids? If you don’t use it, it gets cut off!

First-time feature director Mitchell Lichtenstein—son of the pop artist Roy—has a nice satirical ear for the evangelical subculture (“I’m a virgin,” explains Tobey, “in His eyes”), but he’s not really interested in examining it any longer than he has to so he can get on to his one big shock. That would be the vagina with the teeth. The movie takes great pains—and several websites—to explain the myth of the vagina dentata, and I am happy to endorse the place of this metaphor in literature and movies. (The giant spider in The Lord of the Rings is a particularly good one.) But I’m sorry to say that the symbol only really works when it’s a symbol. An actual girl with actual teeth in her actual ladyparts taps into no deep-seated fears. And even if Lichtenstein—wisely taking a tip from Jaws —declines to show the monster, it still isn’t very scary.

After the first incident, it isn’t all that funny, either. But Teeth contains lots of incidents, as it reveals that every male in sight—Dawn’s secret admirer, her OB/GYN, her stepbrother—is a would-be sexual predator. Guys are lining up around the block to have their dicks snipped off by Dawn. Jess Weixler is an actress whose work I enjoyed a lot last year in a small movie called The Big Bad Swim , and here she channels a pinch of Election -era Reese Witherspoon’s aggressive innocence. But Lichtenstein doesn’t do right by her: Dawn isn’t liberated by her newfound power so much as she’s stuck forever in a gynophobic joke. The audience is trapped with her. It turns out that a one-note movie isn’t very interesting even if that note is played on a vagina.R.