The chief physician at a large metropolitan hospital is formulating a serum to resurrect recently deceased patients. When his facility comes under federal inspection, the doctor is forced to dispose of the "patients" as quickly as possible, even though they are in mid-experiment. With the help of the evil hospital operations manager, he manages to ditch the experiments in a neighboring swamp. Little do they know, the serum works. The experiments come to "life" and wreak havoc on a group of local students conducting science experiments in the swampland. With the help of a hermit, a beautiful innocent bystander, a park ranger, and the police captain, they try to piece together what is going on - as well as how to survive.