In Manhattan, when a client is bitten by a rat in the dressing room of the Garsons Department Store and contracts Weil's disease, the manager Susan Costello is assigned to hire and give all the necessary support to the best exterminator in New York, Jack Carver. The efficient Jack and his assistant Ty find a colony of mutant rats and try to convince the health department administrator and former partner of Jack, Ray Jarrett, how serious the infestation is. But the politician Ray is interested in covering the problem to protect economical interests of powerful groups.

Rachael Newman has developed an interest for murders after she met psycho Patrick Bateman. To further study the subject, she enrolls at the university department for Behavioural and Social Sciences, under the expert leadership of ex-FBI man Robert Starkman. Very certain about herself, Rachael has one single goal: to become class assistant. It's a prestigious job as having that position will almost guarantee employment at the FBI. But becoming class assistant is no easy task to accomplish, as the first trouble arises when secretary Gerty Fleck decides she is too young for it. And Gerty Fleck won't be the only obstacle.

In St. John College, the freshmen and best friends Luke and Roger meet the sexy blond cousins Lilly and Constance in the laundry of their building. They are next-door neighbors, and the experienced girls invite the young men to visit them anytime. Lilly forgets a package of coins in the laundry, and Luke goes to their room to return it. The room is empty, and he sneaks around, when the two girls arrive. Luke hides himself in the wardrobe, and through an opening, he sees Lilly with many tentacles on her breast. Luke tries to convince his friends that the girls are aliens, planning to attack Earth, but nobody believes in him. Meanwhile, some friends of them are found dead, with the internal organs completely frozen.