The horror genre seems to rely on lenient standards. That’s not to say that there aren’t great filmmakers out there making wonderfully frightening movies, but if mediocrity was the only option, box office numbers would hardly flinch. The recent spate of “torture porn” movies prove a constant reminder of this sad truth. Inaugurated by the mediocre Saw movies and sustained with the runaway success of Hostel, these bloody massacres generally manage to bang out a buck as long as heads keep a-rollin', but they rarely muster much in the way of storytelling, mainly because the cringe-inducing label “torture porn” doesn’t refer to anything remotely artistic. Before all else, the films are vehicles, delivering on the implied promise of satisfying our most morbid curiosities.

Building on that promise, Severance -- a British slasher flick about a busload of office mates who wind up stranded in a Hungarian forest at the mercy of maniacs -- operates under the pretentious claim of combining The Office with Shaun of the Dead, but it’s more like watching Hostel in a dark corner while the muted sounds of a Monty Python skit float in from the room next door. The comedy is uneven; the horror is extravagant and largely pointless. As most of the laughs are DOA, you might call this one “torture corn.” (I kill myself sometimes.)

And yet, despite prefacing this review with an overarching gripe, I have to admit that Severance is tightly directed, creating an overall effect not unlike well-wound plastic engulfing moldy bread. Christopher Smith, whose previous directorial credit is the underseen subway stalker flick Creep, pulls together a nifty opener that follows the standard escape-from-the-murderer-in-the-woods routine. The opener leads right into a montage featuring the bumbling busload of salesmen (and terminally defenseless women), each of whom fulfills a stereotype of the slasher genre.

Particular interest should be paid to the goofy stoner (Danny Dyer), the requisite cute American girl with unexpected ass-kicking potential (Laura Harris), and the pudgy office klutz (Andy Nyman), whose moody personality offers much-needed deadpan variety amid all the yelling and screaming about management problems. This trio of characters help the plot make a rather awkward transition from one thinly-executed genre to another. Severance doesn’t elicit yuks through the carnage, nor does it morph into a black comedy. Instead, two layers of moods collide in a raggedy lump of mismatched ideas.

After a few well-placed belly laughs get off the ground, Smith sics his faceless killers (apparently insane asylum escapees) on the quirky protags, and body parts start flying fast. Strangely enough, Severance eventually returns to standard shock mechanisms and abandons its funny bone for the sake of unironic (if reasonably solid) run-scream-slash narrative conventions. The departure in form is a swifter slice than most of the mutilations.

Persistently uneven and aimlessly derivative, Severance nevertheless manages to be entertaining for the duration of its 90-minute running time. There’s something mildly refreshing about watching familiar sitcom personas get hacked to shreds, as though the movie taps into an odd revenge fantasy for audiences who wish they could get rid of the crassest personalities of standard fiction so that only the cool, good looking people stick around. It would make great reality TV.