When 17-year-old Tanja is found murdered in the city of Tromsø, far up in the Norwegian Arctic, National Criminal Investigation Service (Norway) police officers Jonas Engström (Stellan Skarsgård) and Erik Vik (Sverre Anker Ousdal) are called in to investigate. Engström is a police inspector formerly with the Swedish police who moved to Norway after being caught having sex with the main witness in one of his cases. Vik is nearing retirement age, and his memory is failing.