A group of hard-up low level criminals are sent into a giant abandoned school building to fetch stolen goods for the local kingpin. Unfortunately for them, the building is inhabited by the unhinged caretaker Joe and his super strong man-child bodyguard Sunny. One by one the criminals are picked off in increasingly grotesque ways. Heads roll, blood splatters, and gore slops as Sunny tears through the gang like tissue paper. Who will survive and what will be left of them?

After completing their mission in Police academy 2: au boulot! (1985), Officer Carey Mahoney, and the rest of the original graduates from Commandant Eric Lassard's Police Academy (1984) find themselves with their backs to the wall. It seems that, due to funding cutbacks, there can only be one police institution in the city, and Commandants Lassard and Mauser must do their best to get Governor Neilson's approval. Of course, conniving Mauser has already concocted an ingeniously evil plan to...