The friendship between Graham Greene and Kim Philby is one of the most enigmatic of the twentieth century. Greene, the internationally lauded novelist who wrestled with the themes of faith and betrayal in his work. Philby, the British intelligence-officer-turned-spy for the Soviets, and one of the most reviled men of his era. The two men met as young MI6 officers, inseparable in war-torn London working together to defeat the Nazis.But after Greene suddenly resigned just three weeks before D-Day, questions started to arise. He turned back to literature, using his experience in the intelligence services as a backdrop for his novels Our Man in Havana and The Third Man. Lurking within the pages lay suspicions of his friend, with characters and plots echoing Philby's life. Was Philby the real 'third man'? Did Greene's work contain coded messages and warnings of betrayal to M16?In this revelatory book, bestselling author Robert Verkaik chronicles their relationship, spanning the defeat of Nazism and the end of the Cold War, right up until Philby's death in 1988. This is more than just a riveting tale of espionage; it is the story of an unusual friendship that survived against all odds. Ultimately, Greene and Philby explores the perplexing question that no-one yet has answered: why did Graham Greene remain loyal to Britain's most hated traitor?