Between Silk and Cyanide : The Story of SOE's Code War

Between Silk and Cyanide : The Story of SOE's Code War

At the age of 8, Leo Marks discovered the great game of code-making and -breaking in his father's London bookshop, thanks to a first edition of Poe's The Gold-Bug. At 23, as World War II was being played out in earnest, he hoped to use his strengths for the Allies. But Marks's urgent, witty memoir, Between Silk and Cyanide, begins with his failure to get into British Intelligence's cryptographic department. As everyone else on his course heads off to Bletchley Park ("the promised land"), he is sent to what his sergeant terms "some potty outfit in Baker Street, an open house for misfits." In fact, the Special Operations Executive's mandate was, in Churchill's stirring phrase, to "Set Europe Ablaze," and Marks's was to monitor code security so that agents could could report back as safely as possible. When he arrived, the common wisdom was that it was easiest for men and women in the field to memorize and use well-known poems.

Unfortunately, since the Germans had equal access to the classics--"Reference books," Marks quips, "are jackboots when used by cryptographers"--Marks thought agents should write their own poems (or use his) instead, several of which are cheerily obscene. After all, no son or daughter of the Fatherland could ever know the rest of a verse that began "Is de Gaulle's prick / Twelve inches thick," and continued on in a similar, shall we say, vein. But Marks soon felt that original doggerel was just as dangerous, since even slight misspellings could render messages indecipherable and risk agents' lives. His first solution? WOKs (worked-out keys) printed on silk. An operative would use one key, send the message, and immediately tear off the strip. Marks had a hard time proving that swaths of silk would save his people from swallowing their "optional extra," a cyanide pill. His efforts were dead serious, but often landed him in comic terrain.

In one of the book's great set pieces, Marks visits Colonel Wills--surely the model for Ian Fleming's Q--in order to sort out the best ways to print his code keys. Before solving this minor problem (invisible ink!), Wills showed Marks several new projects--one of which involves an exotic array of dung, courtesy of the London Zoo. This gifted gadgetmeister planned to model life-sized reproductions of these droppings and pack them with explosives, personalized for all parts of Europe, Africa, and Asia. "Once trodden on or driven over (hopefully by the enemy) the whole lot would go off with a series of explosions even more violent than the ones which had produced it," Marks explains.

Despite such larky sentences and sections, the author never loses sight of the importance of his vocation, and Between Silk and Cyanide is as elegiac as it is engaging. Marks knows when to cut the laugh track, particularly as his book becomes a despairing record of agents blown--lost to torture, prison, the camps, and execution. Readers will never forget the valor of Violette Szabo, Noor Inayat Kahn, and the White Rabbit himself, Flight Lieutenant Yeo-Thomas. Poem-cracking, as Marks again and again makes clear, was far more than a parlor game. --Kerry Fried