The title, and something of the inspiration, comes from Churchill: ""a great commander [requires] not only massive common sense and reasoning power, not only imagination, but also an element of legerdemain, an original and sinister touch, which leaves the enemy puzzled as well as beaten."" For young people, the book is novel, timely, and especially inspired: how the Allies' myriad espionage activities, and other deceptions, contributed to the winning of World War II. Goldston leads off, suspenset-like, with two British agents boarding the Orient Express for Warsaw in 1938 (there, to check out Polish Jew ""X,"" who claims to be able to build a German Enigma coding machine from memory). Then, he reverts to the interwar years for historical background: the German threat; the Allies' apathy--contrasted, insistently, with Churchill's militance. (The stress does, however, enable Goldston to bring out how much of the preliminary work was ""hidden from the British government."") Once the war begins, covert activities--the use of Ultra decrypts, the ""Intrepid"" (William Stephenson) network in the New World, the ""Tricycle"" snafu (and successful secret-agentry), the climactic Operation Bodyguard (to conceal the site of the French landings)--are integrated with the story of the ongoing conflict. (An interspersed ""War Diary"" makes events easy to follow.) For readers chiefly interested in espionage techniques and spying operations, there may be overmuch historical matter; Goldston, however, wants to stimulate a ""political and moral"" consciousness (which, he observes in his concluding chapter, the CIA lacks), not just to exploit a shady subject. And, as no single adult book has yet done, he provides a sampling, at least, of the vital difference covert operations made in both the European and Pacific wars--requiring only some slight revisions (on Canaris, Stephenson, American ""Magic"") to be fully up-to-date for the lay adult reader too.