The memoir of the most consequential traitor in the history of Western intelligence, written from Moscow in 1967 after his defection. Harold Adrian Russell "Kim" Philby was the ringleader of the Cambridge spies, recruited by Soviet intelligence in the 1930s and installed by the accident of class and charm at the heart of Britain's Secret Intelligence Service. He rose to head the section responsible for Soviet counterintelligence, then served as MI6's liaison to the CIA and FBI in Washington, a position that let him betray essentially every Allied covert operation of the early Cold War, including the doomed insurgencies parachuted into Albania and Ukraine. Philby's account is notable less for what it reveals than for the voice in which it is delivered: urbane, mordantly funny, entirely unrepentant. He writes about his colleagues with the affectionate condescension of a man who found them easy to deceive, and treats his own decades of deception as a professional achievement rather than a moral question. The result introduced a new figure to the literature of espionage, the double agent as ironist, and its influence runs directly through John le Carre's Smiley novels and the later work of Graham Greene, who wrote the introduction. Readers should approach it as both primary source and performance. Philby omits, distorts, and flatters himself throughout, but the omissions are as revealing as the disclosures, and no other document conveys so precisely how the betrayal felt from the inside.