Maria Kallio accepts a temporary position as the leader of the Länsi-Uusimaa Police murder squad. The first murder investigation is complicated by the fact that Maria remotely knows the prime suspect.

While investigating the murder of a young strangled female doctor with her colleague Koivu, Maria Kallio notices how well she gets along with him.

Maria investigates the murder of the chief geologist at a mining company opening event. Maria accepts a permanent position as the leader of the murder squad and moves to her cottage.

The preacher of a spiritual community is found dead and in order to solve the murder, Maria needs the help of Koivu’s new girlfriend, Anni, who works in the financial crimes unit.

Maria immerses herself in her work as she investigates the murder of a young girl from an immigrant family and tracks down a nationalist extremist group. Antti wants to move in with her.

Maria investigates the murder of a poisoned prostitute on live TV. During an arrest, Maria shoots the main perpetrator of a sex trafficking ring, who is also the murder suspect.

A female pedophile released from prison is found dead and Maria traces a perp who is uploading photos and texts into a pedophile network.

A sports boss suffocates in sports gala. As Maria and Koivu investigate the murder, they are lead to a gym keeper who sells steroids.

Maria and Koivu investigate the murder of an antiques dealer stabbed in Hanko. When Koivu is put in mortal danger, Maria realizes how much he means to her.

The brutal murder of Antti's research colleague makes Maria realize that the target of the murder was Antti. Does Maria have time to catch the killer before the killer gets their revenge?