Robin Denniston has uncovered files of diplomatic intercepts which show that Churchill's role in British foreign policy and war planning was far more significant than had been supposed. Although neither a commander-in-chief nor a head of state, he personally exerted considerable influence on British foreign policy to force Turkey into World War II on the side of the Allies. This study also sheds light on Britain's relations with Turkey. The author discloses a plan to open a second front in the Balkans, from Turkey across the eastern Mediterranean, to hasten D-Day in the west. He also reveals new information on the Cicero spy scandal in 1943 when top secret Foreign Office documents were stolen in Ankara by the British Ambassador's valet, who pased then to the Germans.