The Germans have won World War II and the Nazis occupy Britain, dealing harshly with the Resistance. Widowed detective Douglas Archer tries to be impartial and is accused of being a collaborator by his mistress and secretary Sylvia, a member of the Resistance. Douglas is called to investigate the murder of antique shop owner Peter Thomas, who has gunshot wounds but seemingly died of liver failure. Furthermore his shop was a Resistance safe house and he had recently visited a top secret airfield. The killer would seem to be Peter's brother Spode but Douglas is surprised when SS Standartedfuhrer Huth takes over the case, to the annoyance of Douglas's 'boss', General Kellerman, now in charge of the police. Douglas is also intrigued by American journalist Barbara Brarga, who claims to have known the victim only slightly, though Douglas has his suspicions. Written by don @ minifie-1

Douglas learns that Spode is part of the Resistance movement and foils an attempt to make him join by threatening to kidnap his son Douggie but is horrified by the SS's brutal behaviour at Douggie's school. He also finds out that Sylvia colluded with Spode but helps her to escape from the suspicious Kellerman, who shows him a film suggesting that Barbara has enlisted American help to defeat the Germans. Accepting an invitation to a party thrown by art expert Sydney Garin Douglas again encounters Barbara but is also wooed by over a secret card game by a group of high-ranking Resistance sympathizers led by Sir Robert Benson, keen to invite American assistance to expel the invaders. Summoned by Kellerman Douglas acquiesces to a theory regarding Nazi infiltration into the Resistance but, returning home, a disturbing discovery makes him reconsider his allegiance to the conquerors. Written by don @ minifie-1

After the murder of policeman Jimmy Dunn by the Resistance, Harry accuses Douglas of provoking the movement by working for Kellermann and Douglas, having failed to save Sylvia from being arrested, later kills an attacker. He tracks down Spode in an internment camp and whilst Spode admits to killing his brother he is killed himself by German officer Hesse before he can reveal details of the bomb factory. Douglas shadows Hesse to a brothel where he learns that, in collusion with Sir Robert's group, the German army intends to discredit the SS by arranging for the release from prison of King George. Furthermore he gets Barbara to admit that she is a spy, aiming to smuggle the Germans' plans for the bomb to the Americans though she claims no part in the king's escape plan. Next day he is present at Highgate ceremony where the Germans' allies, the Russians, intend to remove Karl Marx's body to a resting place in his native country when there is a bomb explosion. Written by don @ minifie-1

The bomb blast causes many casualties and, as martial law is imposed. Douglas forges papers to take his son to the safety of the unoccupied zone with his neighbour Joyce Sheenan. Returning to work he discovers that Harry has been arrested as a Resistance member but is able to secure his release. Barbara reintroduces him to Sir Robert Benson's group where he learns they are planning to join with the German army in blowing up the bomb factory and freeing the king but need his cooperation. Having sheltered Sylvia after she has escaped from the detention camp he is called to another murder scene, the victim this time being Bernard Staines, a member of Benson's covert Resistance party. Before he can fulfill his obligation he is told that Barbara has been taken by the Germans. Written by don @ minifie-1

Harry and Douglas, helped by Sylvia, rescue the ailing king from hospital and bundle him into an ambulance with a view to sending him to safety in America. A flat tyre leads them to seek assistance at a farm house where they are almost betrayed and need to move on, arranging to meet Resistance leader Mayhew at the airfield. However they have walked into a trap - which at least draws Nazi attention away from the destruction of the bomb factory, as Douglas discovers a lesson in treachery. Douglas is captured and his friends killed whilst Barbara is destined to be deported. Douglas's freedom now depends on Huth, himself doomed to die by Kellermann. Written by don @ minifie-1