The Toxic Avenger is tricked into traveling to Tokyo to search for his estranged father, leaving Tromaville open to complete domination by an evil corporation.

The pupils at a high school next to a nuclear power plant start acting and looking strange after buying contaminated drugs from a plant worker.

A gang of thugs devise a cruel hoax that goes horribly wrong as Melvin, a nerdy emaciated janitor at the local health club, is cast through a third story window into a vat of hazardous toxic waste.