In his Four Just Men series, Edgar Wallace comes up with something different: the villains are not necessarily bad people, and the pursuers of justice, the Four Just Men, as they call themselves, are acting outside the law. They argue that their actions are for the public good, and dispassionately eke the ultimate revenge death on their victims.
Criminal investigating officer Hanne Wilhelmsen considers the possibility of a serial killer as she tracks down a series of numbers written in blood appearing on walls all over Oslo.