Like vaudeville itself, the magic profession was dealt a stiff blow when the first movies appeared. The big stage illusionists, mind readers, escapists, and peddlers of other mirrored trickeration were suddenly in competition with a miraculous spectacle on screens from coast to coast: A light flickering through a loop of film could conjure any thing or action found under the sun, from cowboys robbing a train to Russian sailors mutinying on the Potemkin.

For most magicians and other stage folk, the arrival of movies signaled a coming crisis. But for a magician like the Canadian-born Dai Vernon, it was not a question of one spectacle ousting another. Vernon, the consummate sleight-of-hand artist of his generation, performed his scaled-down brand of trickery for a more intimate audience, often just a rich dinner party gathering or a handful of his fellow professionals. He was a magician’s magician, known to some simply as the man who fooled the great Houdini with a perfect card trick.

A man like Vernon, who performed his art so tantalizingly close up, had less to fear from Hollywood spectacles than from the Depression itself, but he worked from the 1920s almost to his death, at age 98,in 1992. This book (Henry Holt and Co., 368 pages, $26) by the Daily News’s Karl Johnson is the story of how the perfectionist Vernon discovered and relentlessly honed his talent for trickery as a young man in Ottawa, and how as a famous magician he went on a search for a long-rumored cardsharp, or “mechanic,” who could do the impossible – deal from the center of the deck undetected.

This folkloric center dealer was first confirmed for Vernon when he shared a Wichita jail cell with a “Mexican gambler” named Amador Villasenor, who described a dealer in the Midwest who could perform the legendary sleight with perfection. Vernon, then 37, followed Villasenor’s tip through the Kansas City gambling world and further. When he finally found his man in March 1932 – after following the vague description gleaned in the Wichita jail, all the way to the 6-year-old girl who, for the price of an ice cream cone, points out the master dealer’s house in Pleasant Hill, Mo. – it is the sleight-of-hand equivalent of Stanley meeting Livingstone.

Casual readers should be warned, however: This meeting of card virtuosos does not occur until page 215,and those who are not fascinated, as a quirky few of us are, by card lore, the evolution of magic, or the culture of Depression-era gamblers’ dens, may not find the search for Allen Kennedy a compelling enough reason to make the full journey.

Except for his mastery of one breathtaking technique, the life of Kennedy, an underachieving servant of Midnight Underwood’s gambling empire in Pleasant Hill, does not compare favorably with Vernon’s. Although both were perfectionists when it came to improving their card craft, Kennedy never ventured far from his Missouri farm roots, was primarily an overworked tool of gambling houses, and never dared fleece rich targets on cruise ships or in bigger cities.

When Vernon and Kennedy finally met in Kennedy’s house in 1932, the accomplished magician was unable to perceive the cardsharp’s sleight-of-hand. Again and again, Kennedy was able to turn up kings from the center that even to Vernon’s trained eye seemed to slide normally off the top of the deck. After their first meeting, Vernon spent more than a year practicing what he’d struggled to learn that afternoon in Allen Kennedy’s living room. He visited him once more, to show his discovery to his skeptical wife and young son. After that, the two never met again.

Kennedy’s move, Mr. Johnson explains, “was tailored to his world. If he could take a deck, place it on the table for a legitimate cut, pick it up and deal any card he wanted, he would, in effect, conquer that world.” It is not Vernon’s fault that Kennedy failed to conquer that world or that he later slid into a slow death by alcoholism. And Vernon had already established himself professionally at the time he appropriated Kennedy’s life accomplishment. But Mr. Johnson might have been a little tougher on Vernon for his lack of interest in Kennedy in the decades after he’d given up his secret.

Throughout the book, Mr. Johnson creates an interesting contrast between card magicians and gamblers and the arts they practice with cards – magic requires deflection and well-timed flourishes, high-stakes gambling requires that the ruse (the substitution of a card or “gaffed” dice) occur quietly and plainly, without any suspicious movements. Vernon was one of the early practitioners to seek out the low-key secrets of the card table and incorporate them into his own performances, creating a more intimate art of magic. Mr. Johnson’s book, while in some places a victim of its own exhaustive fascination, is a fine dual biography and a vivid portrait of an age of sleight-of-hand geniuses and master cheaters.

Mr. Ward last wrote in these pages on Thomas Fleming.