Teddy. The name is all wrong for the teenager at the centre of this French arthouse horror: a shaven-headed heavy metaller. Teddy is not cuddly nor particularly lovable, but he does turn furry by the light of the full moon. He’s a werewolf, though young film-making brothers Ludovic and Zoran Boukherma are too classy – and sensible – to reveal much more than a flash of bony wolf-foot when Teddy transforms.

The film is in fact a supremely confident genre dice and splice from the Boukhermas: a social realist body-horror black comedy with elements of coming-of-age drama. It reminded me a bit of Julia Ducournau’s cannibal movie Raw, but I’m not sure it’s got quite as much to say. Anthony Bajon is electrifying as Teddy, a high school dropout from a poor family. He lives with his disabled aunt and heavy-drinking uncle (Ludovic Torrent); “We’re the village idiots,” says Teddy. Knowing what everyone in town thinks of his family, Teddy petulantly acts up to the part of mindless yob. He is also the world’s worst temp at massage parlour Ghislaine’s Nimble Fingers, where owner Ghislaine (Noémie Lvovsky) is a lazily predictable stereotype of the gagging-for-it middle-aged woman.

To be fair, most of the characters in the film are pretty hapless, Fargo-style. More funny than Ghislaine are the sleepy local cops investigating a spate of attacks on sheep, which locals believe is the work of a wolf. One night, Teddy goes in the woods and comes out with puncture marks on his back. Next thing you know he is waking up naked covered in blood, with no idea how it got there. Then comes the body hair: the moment he removes a single strand growing out of his eyeball is wince-inducingly horrible.

The Boukhermas don’t sink their teeth into the question of whether the lycanthropy is a metaphor for Teddy’s rage. But their movie ends with a scene of Carrie-style carnage that shows their potential to be cinema’s brothers grim.

• Teddy is released on 5 August on Shudder.