In 1989 a suburban New Jersey town is panicked by a number of deaths from an enormous rattlesnake, only the latest in a series of terrible and violent incidents that seem to be centered around the local high school. Chris Harvey, a social studies teacher dealing with memories of the loss of his fiancee and concerned about keeping his job, is thrust into the middle of it all. He gradually becomes more and more involved until he, helped by some of his students, unravels the mystery and exposes the underlying evil that has engulfed the town.