A Cold Psyche

Two couples meet at a restaurant in Lisbon. One couple is in their 50-60ies, and the other couple, one generation younger. The younger two are Swedes, the older are both naturalized Portuguese with Swedish roots. At this first meeting they know little about each other. The acquaintance persists, and gradually, over a few years, astonishing and unwelcome truths about their connections in the past are revealed. These revelations cause severe tensions particularly unbearable to one of the four. In a shooting incident two of the four are killed. The shooting incident takes place in the deep forests in a rural part of Sweden.
Chief inspector Anders Andersson is assigned to the case. The investigation takes him around the globe, and he unearths many fascinating details. However, to his frustration, Andersson is never able to reveal with certainty who shot whom and why.