Slither

Michael Rooker stars as Grant, a big bald guy from a small southern town who gets possessed by a meat-hungry parasite worm creature from space. Even under the alien influence he still loves his wife, Starla (Elizabeth Banks), but she's alarmed at his weird new habits, such as consuming all the local wildlife. The sheriff in town (Nathan Fillion) investigates. He still carries a torch for Starla from when they were kids, but once the squirming, slithering, and cannibalism begin in earnest, it becomes clear that this is no time for romance. (official distributor synopsis)