Gert Schultheiss, a compulsive gambler who Dr. Franck made ban from casinos in order to protect him, disappears and his wife asks Rainer for help. Matula soon finds him in a gambling den together with his daughter Lissy, who works as a prostitute for Heinz Kottke, her father's bookie, who has both in check due to Schultheiss' gambling debts.—AleX_DJ