What Have They Done to Your Daughters?

After an anonymous phone call, a teenage girl is found hanged in the attic of an old building in Lombardia and the police assume she committed suicide. The efficient Insp. Silvestri and the newcomer Asst. DA Vittoria Stori take on the case, and while checking the location, Insp. Silvestri sees a middle-aged man, Bruno Paglia, taking pictures of the place from a nearby building. The man is arrested and soon Insp. Silvestri learns that the 14-year-old victim, Silvia Polvesi, was part of a teenage prostitution ring which includes Insp. Valentini's beloved daughter. His further investigation with the Asst. DA Stori discover a tape where sexual encounters with important names in Italian society are recorded. Meanwhile, a black-clad motorcycle rider uses a cleaver to get rid of suspects and witnesses.