Jon Favreau, Daniel Stern, ...

“Very Bad Things,” the tale of a bachelor party gone spectacularly wrong, is like “Diner” directed by Oliver Stone from a script by Charles Manson. Kyle Fisher (Jon Favreau), a long-faced Los Angeles yuppie, is all set to marry Laura (Cameron Diaz), a silky, domineering princess who sees her imminent wedding not as a romantic fulfillment but as a victory in the great American popularity-consumerist sweepstakes. Kyle, along with four of his old buddies, heads to Las Vegas for one glorious last blast of “freedom” — i.e., a drug-drenched party-all-night bacchanal, culminating, naturally, in the arrival of a hardbodied stripper/prostitute. When Kyle declines to sleep with her, Michael (Jeremy Piven), high on excess, carries her off to the bathroom for a round of frenzied wall-banging sex. A little too frenzied: As their encounter reaches its climax, he realizes that he has accidentally impaled her on a towel hanger.

Should they call the cops? Boyd (Christian Slater), a real estate salesman who speaks in New Age power-marketing slogans, has a less risky — but far grislier — plan: They’ll remove her body and bury it in the Nevada desert. If only it were that easy. Without revealing too much, let me simply describe the moment when I gave in to “Very Bad Things.” It was during an overhead shot of the bathroom — lots of blood, a mop, a chain saw. (The scrub-the-car episode of “Pulp Fiction” now seemed a cozy bedtime story.) I was utterly appalled. Then, suddenly, I tuned in to the soundtrack, a laid-back groove with the lyrics “I like to party!” The irony, the sheer cheek of it, was too much. In an instant, revulsion dissolved into laughter.

Very Bad Things goes way past outrageous — it’s blasphemous. Yet this Grand Guignol nightmare is packed with rude and clever twists, and it delves, with surprising force, into the hypocritical postures of corporate-era male bonding. In L.A., Kyle and his pals feel as if they’ve been to hell and back, but hell isn’t about to let them escape. One by one, they succumb to guilt and fear, and there’s a gruesome poetic justice to the nearly karmic way in which they’re undermined by their own sins.

“Very Bad Things” is the first feature written and directed by Peter Berg, a veteran actor who has been a regular on “Chicago Hope,” and he has brought off a satanically funny fusion of satire and fever dream. The flowers of evil all lead back to Laura, played by Cameron Diaz with a pitch-perfect manipulative purr. She represents the middle-class obsession with gold-plated nuptial perfection that, according to the film, begets the reactionary decadence of bachelor parties in the first place. The actors, who truly look like desperate, aging suburban frat boys, are all superb. Jon Favreau proves that his puppyish urgency in “Swingers” was no fluke, and I greatly enjoyed the confessional squirmings of Daniel Stern, the family man as walking anxiety attack, and the sublime nonchalance of Christian Slater, who does the finest acting of his career as the delectably heartless Boyd, the sort of guy who can bury a pile of body parts, light up a cigarette, and then say, with just a touch of wistful macho, “It was the smart play.”