During the desperate winter of 1940, as the threat of German invasion hung over England, the British government mounted a massive, secret campaign of propaganda to weaken the isolationist sentiment in America and manipulate the country into entering the war on England's behalf. Under the command of the now legendary INTREPID, the British planted propaganda in American newspapers, covertly influenced radio stations and wire services, and plotted against American corporations doing business with the Third Reich. They also pushed President Roosevelt to create a similar covert intelligence agency in the US, and played a role in the selection of William Donovan as its head. Now for the first time, with great research and reporting, Jennet Conant reveals that the beloved author Roald Dahl was a member of Churchill's infamous dirty tricks squad, and tells the full story of how he was recruited to spy on the Americans during World War II.