A meteor carrying an unknown infection, lands outside a small Californian community, bringing terror and death. Just after midnight, a local rancher named Larry Jenkins discovers the meteor and calls the police. Inspector Bardo is sent to the scene to investigate. The small Lawton police department is shorthanded, as it is the night of the high school prom. Arriving at a desolate forest road miles out of town, Bardo discovers that Jenkins has been infected by the alien organism. The officer is savagely attacked and infected. Both men head towards Lawton, terrorizing and contaminating everyone they encounter. Meanwhile, Cheryl and Timmy have left the prom and are parked atop Lover's Lane. Bardo comes upon the lovebirds and attacks them, infecting Timmy. Now Cheryl must run for her life through the pitch-black forest, escaping her pursuers and trying to reach the authorities before the infection spreads to L.A.