In a tiny California town, high school students Brian (Kevin Dillon), Meg (Shawnee Smith) and Paul (Donovan Leitch) discover a strange, gelatinous substance that melts the flesh of any living creatures in its path. The deadly substance gets into the town's sewer system, where it begins growing uncontrollably, occasionally emerging to feast on unsuspecting townspeople. A military clean-up crew is sent to eliminate the menace, but it may end up doing more harm than good.