Flavia and Fabio, a married couple, are found dead on the dockside in Venice. He was stabbed to death with a huge pair of scissors and she drowned in the process. The police question Flavia's best friend, Marzia, and a series of murders is put in action. A prostitute is stabbed in the crotch; Marzia's lover is shot in the kneecaps before being doused in gasoline and set ablaze; and Marzia herself is tied to a kitchen table and dismembered before being placed in a refrigerator. Meanwhile, extensive flashbacks indicate that Fabio got a strange thrill out of forcing his young wife to participate in horrible sexual acts...