
Criminal investigator Hilkka Mäntymäki faces a new challenge when a young Spanish man and his wife are found shot dead in Oulu, Finland. As the investigation progresses, it turns out that the murdered woman is the daughter of an influential politician in the Canary Islands, and the death in the far north also made the news in Spain.

A Spanish-Finnish couple is found murdered in cold blood in the Oulu region. Hilkka Mäntymäki and the "new sheriff in town" Jami Kalliola start investigating the case.

Hilkka Mäntymäki's team is strengthened by the arrival of Luisa Salinas, flown in from Spain. The investigation leads the police on the trail of a transport company specialising in the waste business.

Hilkka, Luisa and Andrés arrive in Gran Canaria to raid a container that has left Finland. Jami Kalliola continues to investigate the case in Finland. The murders reveal a link to a professionally run smuggling business.

The killer leaves more bodies in their wake. Hilkka and Luisa find barrels full of radioactive mining waste in a storage area abandoned by the army. Andrés meets a man from his past in prison.