Bit of an all-star, "before they were really famous", cast here, with early appearances for Affleck, McGowan and Schreiber - poor Joanna Going must be wondering where she went wrong. Have to admire any film that hits the ground running: five minutes in, when sisters Lisa and Jennifer (McGowan and Going) arrive in a Colorado town, to find it populated solely by corpses. They eventually find live people (Affleck and Schreiber) and have to work out what's going on. "What" turns out to be something that could come straight out of Lovecraft, but in this case was actually from a Dean Koontz book. Toss in a shape-shifting element, as in The Thing, and it's a pretty cool creation, with some impressive KNB effects.
Chappelle's direction is workmanlike and effective, though he's way too fond of the "fake scare, rapidly followed by a real scare" gimmick. However, the main problem is, when you set up such an unstoppable force, you need something equally kick-ass with which to counter it, and this is where the film falls down. Calling in a veteran researcher (Peter O'Toole) is a good idea, and fills in the necessary exposition nicely, but the eventual resolution is about as limp as imaginable - think War of the Worlds, albeit without such blatant deus ex machina. That's a shame, as the idea has a lot of potential, and bottling it up in a remote mountain town doesn't do it adequate justice.