A young woman’s suicide sets off a whole chain of mysterious crimes. Detective Petelina is being blackmailed to destroy a vital piece of evidence. Her former husband has been ruined by a conman, and her close friend is accused of a crime he did not commit. Only a rapid and effective investigation can restore her normal life. And Petelina decides to take a risk. She befriends the killer in order to expose him – but the cunning and respectable criminal figures out her plan.