Judith Loska, a successful pianist, is on tour in New York. Her daughter calls her in fear of death. Someone is threatening to kill her. Judith takes the first plane back but the worst has already happened.
Mrs. Rosen takes groceries to Mr. Mallina and finds him murdered in his apartment. He was supposed to pick an old acquaintance from the railway station later that day. Meanwhile at the station, a young man is asked to carry a suitcase past the inspection.
Ingo and Peter are undercover cops, investigating suspicious activity in a shady bar. Peter gets hired on a gig to drive a lorry, and turns up dead a couple days later. Ingo decides to investigate the case on his own.
A student of a dancing school is found dead in the forest on her way home. A mentally challenged man is seen with her bicycle. Meanwhile, Derrick is not in his best health and must stay aside as Harry and Willi investigate.