The Normandy landings of June 6, 1944 are among the most famous military operations of all time. However, the landings themselves were preceded by a secret war lasting many months. Operating out of London, the British SOE, the American OSS, and the Free French BCRA launched numerous missions to prepare the way for the invasion. Beaches had to be selected and rejected. Tantalizing clues had to be dropped to fool the Germans into concentrating in the wrong regions. The French underground had to be prepared to assist the Allied invaders and impede the Germans. Bridges, crossroads and other key points had to be identified to be either destroyed or captured. No previous author has attempted to cover every special forces unit and every mission launched by the Allies in preparation for the Normandy and Southern France landings. Paul Gaujac, a graduate of France's famed Saint-Cyr military academy, covers all such operations from January to October 1944 in detail, drawing on original interviews and many previously unpublished photographs.