Scapa Flow was the main English naval base during the two world wars of the 20th century. Thanks to its strategic location, it served as a watchtower to control the exit attempts of the German naval units confined to its two main bases in the Baltic and the North Sea. Within the migratory movements that occurred at the end of this war, a German spy could have been infiltrated in the surroundings of the base. In short, a novel that deals with the most interesting chess game of those wars, the one held between the secret agent Weasel and Winston Churchill, cunning against intelligence.