When Cheryl and her roommate quarrel, Cheryl moves into her aunt's skid-row hotel in downtown L.A. rather than return home to Ohio. The lodgers are odd, Aunt Martha is a moralizer obsessed with funerals, murder is afoot, and the inexperienced and trusting Cheryl may be the next victim. She wants to be treated like a woman, and she's drawn to George, a handsome photographer who longs for human contact but sleeps with a water-inflated doll and spies on Cheryl as she bathes. Jeff, a neighborhood clerk, may be Cheryl's only ally in what she doesn't realize is a perilous residence haunted by family secrets. And, what happened to Alice, a model who used to have Cheryl's room?
A group of diverse individuals are suddenly taken from their homes and flown via helicopter to a futuristic bomb shelter in the desert, one-third of a mile below the surface of the Earth. There, they learn that a nuclear holocaust is taking place and that they've been "chosen" by computer to survive in the shelter in order to continue the human race. The shelter is designed to allow the people to exist underground comfortably for years, but they are faced with a threat nobody could have predicted: a colony of thousands of bloodthirsty vampire bats finds a way into the shelter and launches a series of vicious attacks where they claim the humans one by one.