Karppi and Nurmi track down the suspect in the ruins of an old monastery, but the murderer strikes and forces Karp to do desperate acts. The ultimate truth about Carp's death is also clear.

Carp gets new information about her husband's past. The murder investigation takes in the footsteps of Karp and Nurmi's hard-hit family. At the same time, the mystery surrounding the pharmaceutical company is beginning to unfold. Carp realizes that Nurmi is also on the target of the killer.

Karppi, wanted by police, continues to investigate on his own and encounters a disguised murderer. Henna, at the mercy of criminals, has to face death in the eyes. The grass helps Carp get rid of doubts.

The riddle of the symbol takes Karp and Nurmi to investigate the overdose death of a young girl a year ago. Henna is exposed and enters the spring from the ditch. Nurmi gets hold of a video of a dashboard camera shot in Germany that shows a surprise related to Karp's man overrun.

Laura is the target of an assassination attempt and the management of the pharmaceutical company is entangled in a tangle. Karppi and Nurmi find their way to the hideout used by the murderer and at the same time access the traces of the symbol seen in connection with the bodies. The dual role takes Henna deeper into the underworld.

Remains of bodies are found in the sewer, which Carp tries to associate with the murder mystery he is investigating. Laura goes to the hospital and Nurmi starts tracking down the missing Leo boy. Henna is under pressure from both criminals and police.

There are more victims and murders seem to be wrapped around the pharmaceutical industry. Carp gets a dark call from Germany regarding her husband's death. Nurmi meets Laura, who is in serious difficulties and claims to be the father of her child. Henna gives the damn a little finger.

The homicide of a drug scientist placed in a cage forces Karp, who is on leave, back to work and Nurmi to work. The incisions in the back of the body lead to a complex murder mystery. Carp's daughter Henna encounters the miserable daily life of a criminal released from prison.