Corn grain contaminated with steroids produces large rats the size of small dogs who begin feeding on the residents of Toronto. Paul, a college basketball coach, teams up with Kelly, a local health inspector, to uncover the source of the mysterious rat attacks and they eventually try to prevent the opening of a new subway line as well as find the mutant rats nest quickly, or there will be a huge massacre of the entire city!
~ Tonight they will rise from the darkness beneath the city... to feed!