The English intelligence officer Sidney Reilly, who in the first quarter of the 20th century operated in Russia, the Far and Middle East, is called by some the “king of spies”, while others call him a great adventurer. Who exactly was one of the James Bond prototypes? Why did he hide the details of his biography? Did he plan to liquidate Lenin and Trotsky in 1918? Did he die in a shootout with Soviet border guards or was he secretly executed on Stalin's personal orders? And what real feats did he accomplish on the fronts of the secret war? Authoritative British historian Andrew Cook, based on a secret dossier of British intelligence, inaccessible documents from the archives of 15 countries (including Russia and Ukraine), memoirs of contemporaries and the results of twenty years of research, answers these and other questions.