Silver was the codename for the only quintuple spy of the Second World War, spying for the Italians, Germans, Japanese, Soviets and the British. The Germans awarded him the Iron Cross, Germany's highest military decoration, and paid him 2.5 million in today's money. In reality Silver deceived the Nazis on behalf of the Soviets and the British. In 1942 the Russians decided to share Silver with the British, the only time during the war that the Soviets...