The body of 10-year-old Helén Nilsson is found six days after she went missing. Detective Åkesson worries that the investigation is drifting off track.

Pelle is worried that Helén’s case has stalled, when the body of Sofia Jansson is found. Volunteers patrol the streets, including Bengt Karlsson.

The detectives have solved several murders, but not Helén Nilsson’s case. Investigating another murder case, the police think they might have a new suspect.

Pelle secretly reviews Helén Nilsson’s case, and he finds a suspect that bears closer scrutiny: Leif Storm, a neighbor of Helén’s.

Pelle sends a sample of DNA found on Helén’s body to a lab. And once they have the results, the testing of suspects’ DNA can be checked for a match.

A DNA match has identified Helén’s rapist. The police tear apart the suspect’s cabin and find traces of Helén and Jannica’s blood. But is it enough evidence?