It seems the city of Oslo has a serial killer on its hands, and detective Harry Hole is assigned to the case. Only he is not happy with his colleague Tom Waaler, whom he suspects of arms smuggling and murder. A previous Jo Nesbø title was voted best Norwegian crime novel of all time. 

When the Norwegian ambassador to Thailand is found dead in a Bangkok brothel, Inspector Harry Hole is dispatched from Oslo to help hush up the case. But once he arrives Harry discovers that this case is about much more than one random murder. There is something else, something more pervasive, scrabbling around behind the scenes. Or, put another way, for every cockroach you see in your hotel room, there are hundreds behind the walls.

When Harry left Oslo again for Hong Kong - fleeing the traumas of life as a cop - he thought he was there for good. But then the unthinkable happened. The son of the woman he loved, lost, and still loves is arrested for murder: Oleg, the boy Harry helped raise but couldn't help deserting when he fled. Harry has come back to prove that Oleg is not a killer. Barred from rejoining the police force, he sets out on a solitary, increasingly dangerous investigation that takes him deep into the world of the most virulent drug to ever hit the streets.

Christmas shoppers stop to hear a Salvation Army concert on a crowded Oslo street. An explosion cuts through the music and the bitter cold: One of the singers falls dead, shot in the head at point-blank range. Harry Hole - the Oslo Police Department’s best investigator and worst civil servant - has little to work with: no suspect, no weapon, and no motive. But Harry’s troubles will multiply. As the search closes in, the killer becomes increasingly desperate, and Harry’s chase takes him to the most forbidden corners of the former Yugoslavia. Yet it’s when he returns to Oslo that he encounters true darkness....

Two young women are found murdered in Oslo, both drowned in their own blood. Media coverage quickly reaches fever pitch: Could this be the work of a serial killer? The crime scenes offer no coherent clues, the police investigation is stalled, and the one man who might be able to help doesn't want to be found. Traumatized by his last case, Inspector Harry Hole has lost himself in the squalor of Hong Kong's opium dens. Yet when he is compelled, at last, to return to Norway - his father is dying - Harry's buried instincts begin to take over. Then a female MP is discovered brutally murdered.