Reykjavik, August 1941. When a travelling salesman is found murdered in a basement flat, killed by a bullet from a Colt .45, the police initially suspect a member of the Allied occupation force.

The British are in the process of handing over to the Americans and the streets are crawling with servicemen whose relations with the local women are a major cause for concern.

Flovent, Reykjavik's sole detective, is joined by the young military policeman Thorson. Their investigation focuses on a family of German residents, the retired doctor Rudolf Lunden and his estranged son Felix, who is on the run, suspected of being a spy.

Flovent and Thorson race to solve the case and to stay ahead of US counter-intelligence, amid rumours of a possible visit by Churchill. As evidence emerges of dubious experiments carried out on Icelandic schoolboys in the 1930s,Thorson becomes increasingly suspicious of the role played by the murdered man's former girlfriend, Vera, and her British soldier lover.