Detective Inspector Nick Johansson and his partner Sussi, who is also a police officer, are about to separate. In the middle of the move, a cold-blooded murder takes place on the street outside their apartment on Kungsholmen in central Stockholm. Nick is forced to mobilize all the strength and skills he can muster when it turns out that the murder on the street is just the beginning. At the same time, Nick’s colleague Klara Pil is going through an incredibly tough time fighting her demons of illness. However, she is quickly forced to put her own feelings aside, because the killer seems to have started to call in the police team working on this investigation – and is sparing no means.