The date: Aug. 19, 1955. The setting: A cheap hotel room in Schwerin, East Germany. Outside, the wind howls on an unseasonably chilly August evening. A thunderstorm crackles ominously in the distance. Twenty-three-year-old Werner Juretzko has just returned from yet another dangerous mission collecting information for a western military intelligence service. He's tired from a typical day of evasion and deception, and he's about to go to bed. Suddenly,...