June 1940: Hitler has his sights set on Britain, and some British citizens are actually plotting to hasten an invasion. We all know about the heroism of "the Few," but here Robert Hutton tells the equally incredible true story of bank clerk Eric Roberts, who—in the guise of "Jack King"—infiltrated England's fascist organizations. Accessing information that only recently came to light with the opening of MI5's World War II files, Hutton explains how Roberts pretended to be an agent of the Gestapo, gaining a wealth of information to thwart a surprisingly widespread network of Nazi sympathizers.