Spring 1941. Britain, standing alone since Dunkirk; Russia, on the brink of entering the war; America, struggling to stay neutral. And in Germany, after ten years spying for the Americans, Wolfgang Stahl disappears during a Berlin air raid. The Germans think he's dead. The British know he's not. But where is he? MI5 convince US Intelligence that Stahl will head for London, and so recruit England's first reluctant ally into a 'plain clothes partnership'. Captain Cal Cormack, a shy American 'aristocrat', is teamed with Chief Inspector Stilton of Stepney, fat, fifty, and convivial, and between them they scour London, a city awash with spivs and refugees. But then things start to go terribly wrong and, ditched by MI5 and disowned by his embassy, Cal is introduced to his one last hope - Sgt Troy of Scotland Yard . . .