The body of a Russian prostitute was found by the inspector Nina Kautsalo. The blood samples are sent to Helsinki, where Thomas Lorenz, virologist, discovers that they are carrying the deadly virus `Yemen'.

The motorcycle was found in a river, and not with its owner. Nina and Thomas examine the infectious strain of the virus more closely. Marita's sister, Nina, has to be quarantined to protect everyone.

After threatening Nina, Raunola went to the police, pretending to be afraid of an external threat. His test for the Yemeni virus is negative. Only Marita and Evgenya carry the virus.

In Murmansk, Russia, the mysterious Maxim violently interrogates Raunola. In Ivalo, Nina is informed that Thomas was sidelined in the investigation. Together they investigate the list of Marita's sexual partners.

A female speaker arrives at the health centre and dies during childbirth along with her baby, both infected with the virus. The woman's husband admits having visited brothels. Nina and Aikio Hamari are discovered in a remote cabin.

Irina reveals to Nina the behaviour of oligarchs in Murmansk and explains how the young girls were secretly taken to Finland. The young woman looks terrified at the mention of Cevikovic.