Director Juan Carlos Fresnadillo, whose résumé is limited to the deft if wildly precocious thriller Intacto, bluntly raids the zeitgeist in his sequel to Danny Boyle's new-school zombie smash 28 Days Later. That's forgivable because (a) 28 Weeks Later kicks ass; (b) etiquette forbids Nancy Pelosi from discussing the occupation in terms of gore-drenched cannibalistic anarchy; and (c) topical dissent is as intrinsic to the zombie genre as topical skin problems. From the social breakdown of George Romero's Night of the Living Dead (1968) to the undead blowback of Joe Dante's Homecoming (2005), the standard zombie diet has consisted of two delicacies: human flesh—preferably brains and viscera—and subtext, traditionally seasoned with sociopolitical flavor. You are what you eat, and if you happen to eat people, there's bound to be some anthropological gristle to chew.

On the one hand, 28 Weeks Later is a fable of the reconstruction; it might have been called Nation-building of the Damned. On the other hand, so what? As an exercise in pop politics, Zack Snyder's Dawn of the Dead remake cut deeper by replacing the crypto-socialist survival impulse of Romero's original with a total capitulation to cynical, self-serving individualism. That's far more trenchant than Fresnadillo's foreign-policy attack in part because Snyder, a political dunce (cf. 300), wasn't reflecting on ideology from the outside so much as illustrating it from within. Where 28 Weeks Later is allegorical, Snyder's Dawn was frightfully symptomatic.

In any case, Fresnadillo's political disgust is less compelling, and ultimately less emphasized, than his detonation of nuclear family values. In 28 Weeks Later, the war abroad implodes the horror at home. A pre-credit sequence establishes a wrenching betrayal that will ripple throughout the coming storm: Cached in a rural farmhouse under zombie assault, Don abandons his wife in a panic of self-preservation. Later, in London, once he's reunited with his daughters Andy (Mackintosh Muggleton) and Tammy (Imogen Poots), this will come back to bite him—though not, as might be expected, in the literal sense.

Mum's the word on the source of the inevitable zombie infiltration, a neat structural gotcha! that propels an adventure—and a new audience surrogate—outside the green zone. Mention must be made, however, of the superb escalation of tension as the strategy for zombie containment proves inadequate. From a controlled fury of sniper fire to the indiscriminate slaughter of anything that moves, the next step is a doozy: extermination via citywide firebombing and the deployment of chemical weapons. Zombies are the least of it; the prime terror of 28 Weeks Later is a horror of the protocol.

Fresnadillo has a fine sense of scale, shifting from a God's-eye perspective of mushrooming chaos to subjective, street-level reportage, and an uncompromising commitment to unrelenting dread. The sequel trumps its predecessor for sustained doomsday gloom and suggests this might be the man to adapt Cormac McCarthy's post-apocalyptic novel The Road. Dark beyond darkness has settled on Fresnadillo's London as it does on McCarthy's unnamed hell, "like the onset of some cold glaucoma dimming away the world."

Happy times! And superior horror. 28 Months Later can't come too soon.