After shooting a suspected assassin during the approach of the President's convoy, Hole is promoted to inspector and investigates a crime involving a very expensive sniper rifle.
Hole and his colleague, Ellen Gjelten, hear of a man connected to arms dealings called 'The Prince' and set out to learn his identity.
When Hole and his new assistant, Halvorsen, attempt to arrest Olsen, they discover that another police inspector, Tom Waaler, has apparently shot him in self defence.
When Rakel's superior and an elderly woman named Signe Juul are both murdered by the sniper rifle, Hole finds a link between the killings and Norwegian collaborators during the Nazi occupation.
Hole realizes he is wrong when he comes across the actual killer's journal, in which he attacks the Norwegian royal family and other government officials who fled to England during the occupation and who later labeled the collaborators as 'traitors' despite their resistance to the onslaught of the Soviet forces.