Johan Falk is with the wife of a dead mob boss down to Latvia to try to solve a mystery that has eluded him for three years. What Johan finds downstairs in a cottage outside Riga shocks not only himself but also the Gothenburg police special unit GSI 's new chief Sophie Nordh and the former chief Patrik Agrell. At the same time a Latvian mafia group is picking up hidden and forgotten Soviet military containers from the water-filled pits nearby. Containers filled with weapons. And everything is heading to Sweden! At the same time most of the original members of the Rydellgang are being released from a long prison sentence.

The unknown, large mafia organization is now showing its true face. The pressure that GSI and John Falk and his family have put on the organization, makes them fight back on all fronts. The rule book is thrown out. But to go after Johan Falk's family, to try to kill his wife, could be the biggest mistake the organization has done. GSI closes up around Johan's family, and the final battle begins.

Emilka meets the slightly-older Maciek out at a club one night. He shows Emilka—who was brought up by a single mom—a whole new world filled with desire, passion, restlessness and rebellion. The girl moves in with him and at first everything seems just perfect, but gradually Emilka discovers her separate identity, and starts to grow apart from him. When her dream of becoming a singer comes true, Maciek feels threatened. A toxic love game begins, full of lust and jealousy.

Various families experience the ups and downs of their relationships during the Christmas season.