Bäckström is the first to arrive after celebrity lawyer Tomas Eriksson is murdered. The police initially cannot rule out that Bäckström himself is involved.

The murder of Eriksson seems to be difficult to solve, not least when Bäckström is removed from the investigation, and Ankan takes over. Bäckström begins to dig into the beating of Baron Von Comers, suspecting that the two cases are connected.

An old Russian music box made of gold, representing the fairytale character Pinocchio, worth around 300 million kroner, seems to be the motive for the murders. Bäckström is trying to find the music box's former owners.

Ankan begins to question Bäckström's honesty. Eriksson turns out to have been carrying a big secret and now light has just been shed on the night of the murder. Olsson risks ruining the entire investigation in a desperate attempt to impress Ankan.

Bäckström receives death threats and it seems that Tina is the only one who can help him. The police, led by Ankan and Olsson, target Bäckström's best friend in the hope of leading the investigation forward.

Bäckström realizes that he has to hand over Pinocchio to the Russians, the problem is that he doesn't know where the music box is. Ankan finally sees through Bäckström's lies, and the relationship between them is put to the test. Can they still manage to solve the case?

Bäckström travels to Palma, Mallorca, with Niemi to pursue a lead in the murder of his childhood friend Sally, his only unsolved case. Meanwhile, an explosion in central Stockholm may be linked to a drug cartel.

Bäckström turns to unconventional methods to find clues and get around the Spanish police, while Niemi tries to balance the competing interests of Bäckström and Chief Prosecutor Wall.

Bäckström attempts to convince Wall and Toivonen to stay in Palma and continue his investigation, but he has his hands full with two cases that are seemingly intertwined.

When the prime suspect is murdered, Bäckström promises the man's family that he'll find the killer, before he investigates the vineyard's connection to the case.

With new evidence pointing to an unexpected suspect, a large shipment of cocaine is about to arrive in Palma. Wall seeks Morales's help to intercept the shipment before it is smuggled in to Sweden.

Bäckström puts pressure on Mellerud but doesn't get the answers he needs, while Toivonen and Niemi investigate the cartel in Stockholm. Will the truth about Sally's murder finally bring Bäckström peace?