Germany, late summer 1945 - The war is over but the country is in ruins. Millions of refugees and holocaust survivors strive to rebuild their lives in displaced persons camps. Millions of German soldiers and SS men are held captive in primitive conditions in open-air detention centres. Everywhere, civilians are desperate for food and shelter. No one admits to having voted Nazi, yet many are unrepentant. Adolf Hitler is said to have killed himself in his Berlin bunker. But no body was found - and many people believe he is alive. Newspapers are full of stories reporting sightings and theories. Even Stalin, whose own troops captured the bunker, has told President Truman he believes the former Führer is not dead. Day by day, American and British intelligence officers subject senior members of the Nazi regime to gruelling interrogation in their quest for their truth.

Former spy Professor Tom Wilde is enjoying peacetime in Cambridge, settling back into teaching and family life. Until a call from senior MI5 boss Lord Templeman brings him out of retirement.A nearby village has been locked down by the military, its residents blighted by a deadly illness. No one is allowed in or out.There are rumours the Nazi machine is still operational, with links to Unit 731, a notorious Japanese biological warfare research laboratory. But how could they possibly be plotting on British soil - and why?What's more, Wilde and Templeman's names are discovered on a Gestapo kill list. And after a series of assassinations an unthinkable question emerges: could an Englishman be behind the plot?

Winter, 1947. Britain's secret services have been penetrated. The country is more vulnerable than ever - and Soviet leader Joseph Stalin knows it. He decides it is time to send his master of 'Special Tasks' to create extra chaos.But Stalin has a more important motive than mere disruption. He has a man on the inside who must be protected at all costs - a communist super-spy who has the secrets of the atomic bomb at his fingertips.