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.
Timo learns about his grandfather Santeri's background in the workers' sports movement. Inspired by this, he begins to encourage his alcoholic father to practice his own sport, javelin throwing.
