This review contains spoilers.
Typical of the work of Buffy's Joss Whedon, The Cabin in the Woods exhibits a slick flair for genre subverison and manages such with no shortage of pop culture aplomb. No doubt you are aware of the horror movie conventions that constantly strain the credibility of even the most dimwitted of slasher sequels in which teenagers are offed with relative ease: promiscuity ensures death, virginity repels it, and characters who'd likely survive in a group are all but guaranteed to split up like idiots when push comes to shove.
Turns out there's a reason for these ridiculous archetypes: ancient gods, residing deep within the earth, who require a yearly sacrifice -- one ensured by a Big Brother-like organization that ensnares the unwitting for a game of almost certain death (in an amusing touch, global branches of the program function through their respective horror movie trademarks). The agents who control the tightly regimented game (which doubles as a high-stakes reality TV program for the desensitized employees) have access to the monsters and spirits taken for granted by the rest of the world as fiction, as well as the means of manipulating even the most subtle elements of their doomed participants' environments.
At its best, this witty scenario suggests a Haneke-like (or Haneke-light) commentary on audience implication; in the film's reality, these literal snuff films are a required exercise lest nothing less than the end of the world come about. Pity that the film partakes in contrivances as egregious as the conventions it aims to deconstruct; the resulting double standard corrupts the initial appeal of the concept, and reveals The Cabin in the Woods as pretentiously self-serving lip service that assumes hateful mockery of the material it relies upon justifies its own one-note pandering. I'd like to forgive the have-its-cake-and-eat-it-too, excessively ironic self-awareness, but it's hard to overlook the transition from smart to smart-assed and the dispensation of credibility for a weightlessly nihilistic punchline. And that's including the always pleasant presence of Richard Jenkins. Bummer.