Definitive film study of the Normandy invasion - the decision at Teheran, massive preparations, and the landing on June 6, 1944.Definitive film study of the Normandy invasion - the decision at Teheran, massive preparations, and the landing on June 6, 1944.Definitive film study of the Normandy invasion - the decision at Teheran, massive preparations, and the landing on June 6, 1944.