Alexandre Aja's Horns is a biblically tinged, eye-for-an-eye vengeance thriller about an emo boyfriend named Ig (Daniel Radcliffe) whose childhood sweetheart Merrin (Juno Temple) has been murdered underneath the treehouse where they wooed. Ig's not much for self-control or acting innocent, and everyone sees him as Satan -- a point the local paper hammers home with the headline, "Is This the Face of the Devil?" So it's only fitting that, after drunkenly shagging a tattooed blonde (Kelli Garner), he wakes up to find he's sprouted a pair of curving horns. Not only do these spikes make his public image literal, the horns have the ability to pry the truth out of people whether Ig wants to hear it or not. He just has to stand there while the bewitched bug out their eyes, fess up to their worst inner thoughts, and violently make them real. He becomes a hoodie-clad, horn-bespoked gumshoe hunting down the next clue.
The producers were smart to cast Daniel Radcliffe, who's always had the air of a martyr. But Radcliffe wasn't smart to tell the producers yes. This is high-toned horror that doesn't realize it's deeply silly. There's red lights casting hellish shadows on Radcliffe's face and goth covers on the soundtrack (Ig is, of course, an alt-DJ). He can't even break a bottle without the soundtrack caking on a thunderclap.
Most oppressively, every inch of Horns is choked in religious metaphor that strangles the fun from the film. Aja clutters the movie with golden crosses and Garden of Eden snakes, but doesn't dare wrestle with the theology behind them -- this is a snapshot of a steak, not a full meal.