Patient Zero is a perfunctory third chapter in the Cabin Fever series

Porter, it turns out, is immune to the flesh-eating virus, thus making him “patient zero.” Despite Edwards’ reasonable belief that Porter must be experimented on in the hopes of finding a cure before the disease becomes a global catastrophe, Patient Zero nonetheless casts him as a one-note villain more interested in fame than saving lives—a weird dynamic, given that Edwards’ ego can only be satiated by doing what’s in the best interests of the public good. Looking for logic in Wall’s script, unfortunately, is a fool’s game, as his story is primarily defined by been-here, done-that elements, from the romantic predicament of Marcus (who wants to keep his affair with Penny a secret) to Josh’s status as the beer-and-sex party animal. The latter third of the film is full of all-too-familiar scary-movie locales, including the idyllic deserted beach, the blood-stained hidden bunker, the watery subterranean corridor, and the medical examination room filled with grotesque pictures and diagrams.

Aside from one absurdly prolonged sequence involving Marcus reaching for a doorknob, Kaare Andrews’ direction is reasonably efficient. Yet it’s constantly undercut by uninventive plotting. There’s no suspense to Patient Zero, just the increasingly dreary sense of heading toward conflicts that will end in rote gruesomeness. The gore does eventually arrive in spades, but even that seems half-hearted, as if the filmmakers, finally out of ideas, have chosen to simply give their niche target audience what it wants. Regrettably, that sort of adherence to formula makes this third Cabin Fever feel simply unnecessary, save for the one moment—in which a hand magically breaks off an arm and flips it in the air, so that the gun it’s holding can shoot a man in the face—when it also proves downright inane.