During a snowy Christmas season in Sweden, psychologist and criminal profiler Inger Johanne Vik finds herself and her autistic daughter drawn into an investigation surrounding a series of brutal killings.

Detective Ingvar Nyman of the Swedish national police force is dispatched to Uppsala to investigate the shocking killing of Bishop Elisabeth Lindgren.

The police have finally discovered the body of murdered TV chef Isabella Levin, while the killer continues in his pursuit of young witness Stina Vik. Stina's mother Inger Johanne joins the investigation.

The police hear the results of the autopsy on the body of artist Niclas Rosen. The investigation now involves three seemingly unfathomable murders, but a link slowly starts to emerge.

More violence is unleashed, as police begin to grapple with what they now believe is a homophobic motive. They start to trace the case back to an American organisation of religious Christian fanatics who take contracts out on homosexuals.

The noose is tightening around Marcus Stahl, who also finds himself unjustly suspected of murder. Meanwhile, the secret of Bishop Elisabeth Lindgren can no longer be kept under wraps, as police probe further and her widowed husband buckles under the pressure.

Inger Johanne continues to use her expertise and intuition to piece the puzzle together. But, as she gets closer to understanding the killer's frame of mind, the killer gets closer to her too.

Inger Johanne and Ingvar finally have a clear picture of the killer's identity and motive, but - with one last killing outstanding on the murderous contract and the tension ratcheting up - the two can't agree on the best way to proceed. Who is next on the list to be murdered?