For decades, rumors of top-secret "magic" manuals swirled within CIA circles.
The long-lost guides were said to have been written by a prominent magician, but many officers dismissed them as myth, believing them too fantastical to be true.
But in 2007, retired CIA officer Robert Wallace unearthed an extraordinary archived file and is now making its contents available to the public for the first time.
It was thought that every copy of his reports had been destroyed in 1973.
But Wallace obtained surviving copies and, with intelligence historian H. Keith Melton, combined the two manuals -- one examining sleight of hand techniques and the other on covert signaling -- into one book, recently released by publisher HarperCollins.
Complete with illustrations, "The Official C.I.A. Manual of Trickery and Deception" describes a wide range of Mulholland's Houdini-like tricks designed to help spies pull off a number of clandestine operations, such as slipping poison into an enemy's drink or surreptitiously removing documents.
Other magician-historians previously established Mulholland's connection to the CIA and printed portions of his reports – and one, Michael Edwards, said he received full copies of the reports from the CIA in 2003. But the authors say their book is the first to publish the historical documents in their entirety.