A large comet is hurtling toward Earth. The President of the United States initiates a world-wide nuclear weapons launch to stop it. David Dematti, a water treatment facility shift leader, discovers that the meteors have polluted the water supply of the southwestern United States, causing a strange and deadly sickness. He tries to learn more, but he is almost killed when a meteor shower destroys his water treatment facility. When David's family is taken into forced quarantine, he tries to follow their police convoy to Las Vegas but is stopped by a meteor shower. David and Lin Lee, a young woman poisoned by the water, team up to fight these apocalyptic disasters and save their families.