Der kalte Finger (1996)

Conny works at a hospital switchboard during the day and for a phone-sex agency in the evenings. She regularly talks on the phone with someone who calls himself the Cold Finger. Because she also provides him with the agency’s service from home, the agency’s boss sends a thug after her, since she is poaching clients and working on her own account. Conny’s boyfriend, Gregor, learns about her double life only after her confrontation with the thug. After two women’s bodies are found, Conny realizes that the Cold Finger is a serial killer who turns his sexual fantasies into deadly reality, and that he wants to possess and kill her at any cost. The Cold Finger pretends to be an artist and lures Conny and Bibi to a hotel room with offers of large sums of money. After her colleague Bibi is murdered, Conny serves as a police decoy. But the Cold Finger still manages to get Conny under his control. As he tries to escape with Conny on a motorcycle, police shoot him on the roof of a hotel and arrest him. The film ends with Conny having moved in with Gregor and receiving a phone call from the Cold Finger in prison.