Kaboom is full of charming characters. Like the lunkhead surfer who tries to blow himself. And the edgy “vagitarian” who charms by dispensing phrases like “sucking a fart out of a dead seagull’s ass.” And then there’s our main guy, the greasy-haired Smith, whose “undeclared” sexual orientation means he can screw guys and girls, occasionally at the same time.

Copulation, in fact, practically overcomes the alleged premise of writer-director Gregg Araki’s college-set thriller. All these characters do is fuck each other. And it’s exactly the opposite of exciting—the bedroom (and beach and car) scenes are tedious and, teenage hormones notwithstanding, borderline unbelievable.

Unless, of course, Araki intended Kaboom to be soft-core porn. But it seems like the Mysterious Skin director did actually try to make a genuine movie—it’s just a bad one. The plot centers on Smith (Thomas Dekker), a nearly 19-year-old who lusts after his roommate, the improbably named Thor (Chris Zylka), but spends most of his time with his vag-loving best friend, Stella (Haley Bennett). Smith never knew his daddy but one day receives a nicely engraved note with the message, “You are the chosen son,” a possible clue to his past.

For most of the film, however, the central mystery involves a homicide that Smith may or may not have witnessed. High on a cocktail of drugs, Smith thinks he sees the murder of a red-headed girl (who’s been appearing in his dreams) by a group of mask-clad ne’er-do-wells. He passes out, though, and the next day there’s no sign of bloodshed, so he starts to believe he may have hallucinated the whole thing.

Tons of sex and conveniently interlocking tidbits later, and Kaboom is now about cults, the apocalypse, and the type of twists that have characters blubbering “I’m not sure what I believe anymore!” (Actual line.) One of the more interesting and, amazingly, less far-out subplots involves Stella’s ex, a witch who doesn’t suffer breakups gladly. Her powers are kinda creepy and of the magnitude that renders restraining orders useless. Other than that, it’s difficult to talk about developments in the plot without giving too much away. So let’s just say: They’re stupid, the characters are irritating, and no one here will have to worry about delivering an Oscar speech for their contribution to this horny mess.