Kim Philby is perhaps the most notorious traitor in British history and the archetypal spy: ingenious, charming, and deceitful. Reexamining Philby's early years, Edward Harrison uses documents from the United Kingdom National Archives and newly discovered private papers to uncover a pattern of deception that began with a betrayal of Philby's own father, St John Philby. This engaging biography deftly navigates the half-truths of Philby's own account of his actions in his memoirs, The Silent War, and explores his time in Spain and working as a counter-espionage officer in World War II. Essential reading for students and scholars of modern history, Young Philby distils Harrison's extensive research into an exciting and explosive narrative.