A rich widow is found dead in her apartment in Helsinki due to gas poisoning. The incident is initially thought to be an accident, but inspector Palmu notices that the murderer made a mistake, and so Palmu, Kokki and Virta begin the investigation: who had come to the apartment through the balcony door and opened the gas tap while Mrs. Skrof was asleep?
The headmaster of a private girls' school is doing her best to maintain strict discipline in the school. In addition to the loosening morals of the students, the warm relationship between two girls is a causing concern.
An ex-finnish army officer Kari Kivi returns to Finland after 12 years of absence. He is quickly hired by a businessman named Östermalm to be his stand-in to escape the ring of spies threatening his life. Many beautiful women cross Kivi's path before the spy ring is eventually crushed.