I wrote The Confidence Men to solve a hundred-year-old mystery.

The book, a nonfiction thriller coming out on June 1, centers on a remarkable real-life hoax: During World War I, two British officers escaped from a remote Turkish P.O.W. camp … by means of a Ouija board.

I first encountered their story several years ago, in the most satisfying way possible: thumbing through a dusty, long-out-of-print book looking for something else. What caught my eye, though, was an essay with the most tantalizing title I had ever seen on any piece of nonfiction: “The Invisible Accomplice.” How could one not read anything under a rubric like that?

The essay did not disappoint. Written by one of the two escapees, Elias Henry Jones, and originally published in the 1930s, it recounted his escapade in brief. Jones’s essay led me in turn to his full-length memoir, The Road to En-Dor. Published in 1919, the book was intended as a cautionary tale about how breathtakingly easy it is to become a spiritualist charlatan, a species of war profiteer that flourished between 1914 and 1918 to wring dividends from gold-star families. (Jones’s title is a nod to “En-Dor,” Rudyard Kipling’s bitter poem of 1919. In it, Kipling, who had lost a son in World War I, decries such mountebanks: “The road to En-dor is easy to tread/For Mother or yearning Wife./There, it is sure, we shall meet our Dead/As they were even in life. …” Kipling’s title invokes the biblical Witch of Endor, from the First Book of Samuel, whom Saul asks to conjure Samuel’s spirit.)

Long after I finished Jones’s book, two things haunted me. The first was that this astounding story, full of cunning, mortal danger and moments of wild farce that rival anything in Catch-22, had been largely forgotten by history. The second was that the tale had at its center an enduring mystery: How in the world was an escape via Ouija board—a preposterous strategy in every respect— actually able to succeed?

The plan seemed born of delirium. Using a handmade Ouija board, Jones and a fellow captive, Cedric Hill, would gradually seduce their Ottoman captors with a meticulously engineered confidence game, spun out over more than year. Their con—an elaborate piece of participatory theater entailing candlelit séances, secret codes, magical illusions and a hunt for buried treasure, with clues seemingly planted by ghosts—was designed to make the captors wild to lead them out of Yozgad, a POW camp high in the mountains of Anatolia. If all went according to plan, Yozgad’s iron-fisted commandant would personally conduct Jones and Hill along the road to freedom, with the Ottoman government paying their travel expenses. If their con was discovered, it would mean a bullet in the back for each of them.

The hoax also required Jones and Hill to feign insanity, stage a joint suicide attempt that came heart-stoppingly close to turning real, and spend six months in a Turkish insane asylum. Yet in the end they won their freedom.

Jones was the scheme’s principal architect, and his memoir dwells almost microscopically on how the ruse worked, detailing a web of planning, rehearsal and performance. There is less analysis, however, of why. (Hill’s memoir, The Spook and the Commandant, published posthumously in 1975, also favors exposition over explanation.)

But it was the why of this astounding story that pulled at me: I grew determined to discover the precise ingredients of the psychological cocktail that, Jones wrote, let him transform his captors into “clay in the potter’s hands.” With benefit of a century’s hindsight, I’ve had the privilege of doing just that in The Confidence Men, setting the caper in historical and psychological context—and in so doing, solving the mystery at the story’s heart.

Besides chronicling one of the most ingenious hoaxes ever perpetrated (and one of the only recorded examples of a con game being used for good instead of ill), The Confidence Men explores the psychological gambit that undergirds all con games: the delicate process of mind control called coercive persuasion—colloquially known as brainwashing.

The book is also a window onto a pivotal moment in Western history: an era awash in magicians, mentalists and mountebanks of every stripe; a time when widespread belief in the spirit world stood shoulder to shoulder with groundbreaking developments in science; when the understanding of mental disorders was poised between 19^th-century alienism and 20^th-century Freudianism; and when miracles of disembodied communication like telegraphy, radio, and the telephone made the possibility of discourse with the dead a legitimate empirical question.

But while Jones and Hill’s story reveals much about the early 20^th century, it also illuminates the 21st. Coercive persuasion is the modus operandi of contemporary figures like advertisers, salespeople, cult leaders, magicians, and political firebrands. My book’s central questions—How does a master manipulator create and sustain faith? Why do his converts persist in believing things that are patently false?—turn out to apply equally to a mountebank at a Ouija board, a conjurer staging an illusion, and a demagogue swaying an electorate. Mastery of the psychology of deception is indispensable to each.

Above all, The Confidence Men is the story of the profound friendship between two men who almost certainly would not have met otherwise: Jones, the Oxford-educated son of a British lord, and Hill, a mechanic on an Australian sheep ranch. Vowing to see the scheme through if it cost them their lives, each was sustained throughout its myriad hardships by the steadfastness of the other. “For a brief period,” Jones would write, recalling their six-month confinement in the madhouse, “Hill was put in the bed next mine. It seems a little thing, that we should lie there three feet apart instead of ten, but it meant much. … We did not attempt to talk—we were too closely watched for that—but at night, under cover of darkness, sometimes he and sometimes I would stretch out an arm, and for a brief moment grip the other’s hand. The firm strong pressure of my comrade’s fingers used to put everything right.”

Margalit Fox (@margalitfox) is a former senior writer at The New York Times. Her new book, The Confidence Men: How Two Prisoners of War Engineered the Most Remarkable Escape in History, will be published by Random House on June 1.

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