The chair of the Malmo city council is found dead right on the Danish-Swedish border on the Øresund bridge between Copenhagen and Malmo - the corpse cut in half at the waistline. Detective Saga Norén of Malmo CID is applied to the case and soon learns that the lower half of the corpse belongs to a yet unknown Danish woman. She is forced to team up with her Danish colleague Martin Rohde, who is slightly irritated by her unusual manners. At the same time, Göran Söringer is brought to Copenhagen's Rigshospitalet to receive a heart transplant.

The hunt is on for the leader of the eco-terrorists, with Saga and Martin hoping to stop any further attacks from happening.

A sunken boat containing skeletal remains is found, that appears to be related to the eco-terrorist case. Martin's son is taken into hospital in a serious condition.

Saga and Martin have a sketch of the suspect, but can they get to them in time to avert 'The Graduation'. Their friendship is placed under strain by Martins inquiry into Saga's past.

It becomes apparent that the case isn't over and Saga and Martin race to prevent another terrorist attack. Saga faces a decision that may destroy her friendship with Martin.

With the detectives now working on two so-called 'clown murders', a prime suspect is the traumatised son of the first victim, who is on the run. The usually phlegmatic Saga is distracted from the investigation by the unwelcome appearance of her mother, who insists on showing her a medical file, hoping to find a resolution to their estrangement.

A sceptical Henrik and Saga are initially unimpressed when a young art curator suggests a connection between the murders of Helle Anker and Lars-Ove Abrahamsson and the brutal attack on Hans, but his theory leads them to interview Freddie Holst, a successful businessman with a substantial art collection. The detectives are called to yet another victim whose mutilation seems to be the work of their serial killer.