Very little has ever been written about Renato Levi, or his incomparable contribution to the Allied war effort, simply because his role has been kept so secret. Even with the declassification of MI5's wartime files, all references to his true identity were redacted. However, it is now possible to tell his astonishing story in full for the very first time since his death in 1954. As a double agent Levi, or 'Cheese' as he was codenamed, has few equals. He was an Italian Jew brought up in India, educated in Switzerland, and employed as a British agent while working for the French, Italian and German intelligence services.  During his espionage career, which spanned the entirety of World War Two, he worked for four intelligence agencies simultaneously and miraculously survived the experience.