He Was The First Hero Of World War II And Yet The American Public Has Never Seen His Face.

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Simon & Schuster



In 1940, with Nazi Germany on the march, William G. Sebold, a naturalized American of German birth, risked his life to become the first double agent in the history of the FBI. Intensely patriotic and cool under pressure, he spent sixteen months in the Nazi underground of New York City, consorting with a colorful cast of spies that included rowdy sailors on shore leave, a Jewish femme fatale, high-level engineers privy to America’s most valuable military secrets, and a South African soldier of fortune with an exotic accent and a monocle.

The nest of Nazi intrigue was closely monitored by German spymasters intent on gaining a techno-logical edge for the Luftwaffe bombers terrorizing Europe. Meanwhile, Sebold found himself at the center of a sophisticated FBI investigation that established a short-wave radio station on Long Island to communicate with Hamburg spymasters and then set up a “research office” in Times Square that allowed agents to film meetings between Sebold and the German spies.

The monumental result of Sebold’s work was the arrest and conviction of thirty-three spies, still the largest espionage case in American history. The guilty verdicts were announced in Brooklyn federal court just hours after Adolf Hitler defiantly declared war on the United States on December 11, 1941, which meant that the Führer could not call upon a small army of embedded Nazi spies and saboteurs during the most trying days of the coming struggle. “As you know,” an FBI official later told J. Edgar Hoover, “Sebold gave us the most outstanding case in Bureau history.”

Then Sebold disappeared into an early version of the witness protection program, never to be heard from again. His story, one of the great spy yarns of World War II, has remained untold—until now.

Hailed as a “captivating” (San Francisco Chronicle) and “masterful” (Publisher’s Weekly) storyteller, Peter Duffy has unearthed a wealth of original research, including thousands of pages  of FBI files, and crafted Sebold’s story in fascinating and vivid detail. An accomplished journalist and historian, Duffy once again delivers a narrative with “the grip of good fiction and the punch of hard truth” (Chicago Tribune). Fantastically fast-paced, Double Agent unveils the thrilling story of one of the most successful FBI counter-espionage  operations in American history.

Rich with eccentric characters, suspense, and details of spycraft in the war’s early days…. The result is a compelling cultural history with all the intricacy and intrigue of a good spy novel.Boston Globe
Intriguing account of the unraveling of the German intelligence network in the U.S…. thrilling.Wall Street Journal
Peter Duffy brings out of the cold — well, out of the shadows — a spy who is not only a hero like Bond, but also a man who was never there… Duffy allows the reader not only into the innermost workings of the investigation, but also to connect with the protagonist Sebold and see the aftermath in a truly human hero.Pittsburgh Post-Gazette
Double Agent is an important and impressively researched account of a still little-known man who made a big difference in the world of counterintelligence. Duffy reveals new information, much of it from thousands of pages of FBI documents… Both timely and significant.Dan's Papers, (Hamptons)
The grip of good fiction and the punch of hard truth.Chicago Tribune
The intrigues of Sebold and his minders, vividly depicted by Peter Duffy, read at times like a John le Carré novel. There is a gray, dank sense of boredom in a spy’s daily existence, along with a frisson of reckless endangerment, both of which Duffy conveys through a plethora of historical detail.
Peter Duffy’s Double Agent exposes the shocking extent of German espionage in America on the eve of World War II with dazzling new research and deft historical insight. A riveting non-fiction thriller that exposes history’s neglect of William Sebold, an unjustly forgotten American hero. Duffy offers still relevant insights into the boundaries of civilian surveillance and FDR’s and J. Edgar Hoover’s handling of intelligence information to influence public opinion.Jerrold L. Schecter, Cold War historian and coauthor of The Spy Who Saved the World: How a Soviet Colonel Changed the Course of the Cold War
Peter Duffy absorbingly recounts the true story of William G. Sebold… right on target.The New York Times
Duffy tracks Sebold’s efforts with a tense, exciting narrative filled with a motley collection of characters, some sinister and some unlikely as villains. This has all the elements of a fine spy novel, with the bonus that it is all true. Booklist
Thrilling, well-researched, well-told, fascinating.Minneapolis Star Tribune
One of the great spy missions of American history.Publishers Weekly
Immensely readable… Colorful personalities proliferate throughout the narrative, the understated character of Sebold gleams. An entertaining work duly informed by Duffy’s knowledge of both the war and New York City.Kirkus
Double Agent is worth reading.Washington Post

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