On February 7, 2003, opening day of the San Francisco antiquarian book fair, Ken Sanders warily paced his booth. He was surrounded by some of his treasures, including The Strategy of Peace inscribed by John F. Kennedy and a first edition of the Book of Mormon. With his long black-and-white beard, thinning ponytail, and ample paunch, Sanders didn't resemble the many bow-tied, blue-blazered dealers at the fair, and he didn't share their anticipatory excitement. Instead, as security chief of the Antiquarian Booksellers' Association of America (ABAA), he was haunted by the fear that John Charles Gilkey, the elusive book thief he'd pursued for three years, the rogue collector who'd just posted bail, might be brazen enough to show up.

Sanders, now 54, watched as collectors drifted from one book dealer to the next, gazed into glass cases, and asked to hold in their hands venerable volumes like William Wordsworth's The Prelude ($65,000). They consulted maps of the fair floor, squinted through spectables across booths, and stooped to better run their eyes down the spines of books, eager to locate, say, a signed first edition of Harry Potter and the Sorcerer's Stone or Lewis Carroll's copy of the 1482 edition of Euclid's Elements, one of the great mathematical texts (both of which were for sale that day for $30,000 and $175,000, respectively). They also roamed the aisles hoping to be surprised, because that's what rare book collectors live for, to stumble upon a book whose scarcity or beauty or history or provenance is more seductive than the story printed between its covers. It was in the midst of this literary sleuthing that Sanders locked eyes with a man he didn't recognize. "I had the weirdest goddamn feeling," he remembers, "but I couldn't place the guy." So he turned to his daughter, Melissa, to ask if she recalled whether this stranger was perhaps a customer they'd met before, and not Gilkey, as he suspected. But by the time Sanders turned back, the man had vanished.

Gilkey did stop by Sanders's booth that day, but after strolling up and down the aisles for about 45 minutes, he started to feel as though he was being watched. "As I passed one booth, I heard a woman say, 'He could go to jail for that.'" says Gilkey, "and I thought she might be talking about me" So he slipped out of the fair, carrying under his arm a book he had been hoping to sell to an unsuspecting dealer. It was a copy of H.G. Wells's The Invisible Man.

People have been collecting¡ªand stealing¡ªbooks ever since they were made available to secular society in ancient times. These days, the Bay Area is among the hottest places in the country for book collecting (the San Francisco antiquarian book fair, for example, is larger and more diverse than those in Los Angeles, Boston, and New York). Shops may be elegant, old-world havens, like John Windle Antiquarian Bookseller near Union Square, or the offbeat and slightly disheveled Argonaut Book Shop on Sutter Street, which specializes in books on California and the American West. Many used bookstores also have small rare-book offerings.

Book collectors¡ªthe most ardent referred to as bibliomaniacs¡ªare a passionate, determined breed. As A.S.W. Rosenbach, the most famous 20th-century rare book dealer, said, "I have known men to hazard their fortunes, go long journeys halfway around the world, forget friendships, even lie, cheat, and steal, all for the gain of a book." Fortunately for the trade (and collectors' friends), most of them simply go prospecting at fairs and stores. They read bibliographies of authors and devour any material they can find on genres of interest: medical texts, children's books, California history, WWII, incunabula (books printed before 1501), Pulitzer Prize winners, erotica (although, according to one dealer I spoke with, most ABAA dealers "leave that to the Europeans"), and more. There is probably no subject, author, illustrator, or specialty printer whose books are not collected, and no potential venue¡ªGoodwill, yard sale, estate sale¡ªthat goes unscoured. You never know when someone may have tossed dear, departed Grandpa's first edition of Fitzgerald's Tender Is the Night into the Salvation Army trailer, unaware of its value (with a first-issue dust jacket, about $45,000).

As much as such prices might set a gold digger's heart racing, they are not usually what motivates book collectors, whose relationship to their objects of desire is varied and complex. At a Boston fair in October, I heard a dealer with an impressive selection of dust jacket art say, "Don't judge a book by its content." However tongue-in-cheek, this twisted aphorism exposes the curious fact that many collectors don't actualy read their books. Yet many have a scholarly interest in a particular subject, amassing copious quantities of books¡ªon the Vietnam War, for example, or cookbooks from Colonial times¡ªwhich they may one day bequeath to a library or other institution. For some, possession of the book provides a physical link to a period in time, often their own childhood, or to an author who may have touched the very same pages. For others, it is the book as talisman of knowledge and affluence that both satisfies and spikes their lust for more¡ªand, in a very few cases, lures them to what Sanders calls "the mythical dark side."

Case in point: John Gilkey. Like most collectors, he's not in it for the money. Nor does he read the books he's acquired. But his interest in books has gone from being a pastime to a full-blown obsession. In the Bay Area, no one book thief has been as prolific. And no one has been as determined to catch him as Ken Sanders.

One of Gilkey's earliest known thefts in the city happened on March 14, 2001, at the Brick Row Book Shop on Geary Street. At the time, the owner John Crichton didn't know it was Gilkey¡ªthat wouldn't become clear until much later. He says a man who identified himself as Dan Weaver called the store and asked if they had a first edition of Thomas Hardy's The Mayor of Casterbridge. They did, for $2,500. Later that day, an older man whom Crichton describes as "in his late 70s, not looking real sharp" came into the store and said he was there to pick up a book for his son. He was abrupt and seemed rushed. "I'm in a hurry," he scowled, "double-parked. I gotta get the book." Chrichton checked to make sure the credit card charge had gone through. It had, so he handed over the book.

A month later, Crichton discovered that the charge was fraudulent, made to a stolen credit card number. He notified Sanders in Salt Lake City, who had begun hearing similar reports. Dealers always recounted the same scenario: a man would call and inquire about a book or two, chat for a while, settle on a price, sometimes ask about where to have a clamshell box (a protective case) made for it, and pay by credit card. The charges whould be in the hundreds or thousands of dollars, but never more than $10,000. The caller would say that either he, his father, son, nephew, or brother would pick the books up. The question in Sander's mind at that point was why dealers sometimes described the thief as a man in his 30s, other times as a man in his 50s, and still other times as a man in his 70s. Was this an individual or a gang? Even more perplexing was that neither The Mayor of Casterbridge nor any of the other books that had gone missing in the same way were showing up for sale anywhere¡ªnot at dealers' shops, not at book fairs, not on the Internet.

Sanders, who jokingly calls himself "the book cop," has been collecting and dealing in books for most of his life. His father likes to say he was born clutching a book. As a child, he braved the glare of the neighborhood's irascible junk store owner in order to reach, on tiptoe, into a lard barrel full of olf comic books. He started selling books as a teenager. His current store is Ken Sanders Rare Books, which his friend "Captain Eddie" (artist Ed Batemen) says is the nexus of Salt Lake City's counterculture. It's a 4,000-square-foot, sun-filled former tire shop, with over 100,000 books and old paintings, maps, photographs, postcards, posters¡ªand a seemingly endless supply of impassioned conversation that revs up around 5 p.m., when Sanders offers drinks from a small fridge next to the counter. More than one friend of Sanders describes him as a man of extremes. When he is not reading books or selling books or going after people who steal books, he is white-water rafting or exploring Utah's deserts or planning his annual "burning cow festival," which his friend and ABAA past president Ken Lopez has heard described as "about four notches weirder than Burning Man and three notches less commercial."

Like many book dealers, Sanders is also a spinner of yarns. But the difference between him and most of the dealers I've met is the force of his narratives: like tornadoes. In a style that gathers its momentum from equal measures of rage (toward the thieves) and protectiveness (toward his colleagues), he has told me about various thieves he's caught or helped to catch or still hopes to catch. There's the Red Jaguar Guy, who stole valuable copies of the Book of Mormon from him and several other dealers; the Irish Gas Station Gang, which routinely places fraudulent orders with dealers through the Internet and has the items shipped to a gas station in Northern Ireland; and the Venezuelan, a dapper con artist who's pilfered from several high-end dealers. There are countless others, but the story Sanders has probably told most often is that of Gilkey, whose criminal ingenuity and tenacity matched his own ardor for catching him. With characteristic fervor, Sanders wanted to stop the scoundrel who had been robbing his friends.

When Sanders started working as security chief in 1999, he had no idea how fully his pursuit of thieves, especially Gilkey, would consume him. But soon after he received word of the theft from Crichton's shop, he began getting fraud reports from a number of dealers in Northern California. The Patchwork Girl of Oz by L. Frank Baum ($1,800) and a signed two-volume Joesph in Egypt by Thomas Mann ($850) were stolen from Heldfond Book Gallery in San Anselmo, and a Lord Jim by Joseph Conrad ($3,000) was stolen from Robert Dagg Rare Books in San Francisco. These dealers had been swindled by somone using the same MO as in the Brick Row case: payment was made with a stolen credit card number, it was weeks or months before the cardholder was notified, and the dealers had to eat the cost of the book.

In 2002, theft reports from Northern California slowed down, but other regions began reporting losses. Ed Smith Books in Washington State, for example, reported losing a first edition of Joseph Heller's Catch 22 ($3,500) and a signed limited edition of Samuel Beckett's No's Knife ($850). Kevin Johnson of Royal Books in Maryland reported losing Jack Kerouac's On the Road ($4,500). In both cases, one detail in the thief's method had changed: rather than telling dealers that he or a relative would pick up the books, he requested that the books be mailed overnight. The addesses he gave were later discoverd to be hotels in the Bay Area. With this new twist, Sanders started referring to the perpetrator as the Nor Cal Hotel-Motel Credit Card Thief. He also started t believe that the thief was a collector who in fact had gone to the dark side, because the books were not being offered for sale anywhere. If this person was a collector, Sanders knew that catching him, or her, would be very difficult.

I first met John Gilkey in the spring of 2005 while he was an inmate at Deuel Vocational Institution in Tracy. A native of Modesto, he is 37, about five feets, eight inches, with long, nail-bitten fingers and thinning dark brown hair that he takes a black plastic comb to whenever he removes his baseball cap. He is soft-spoken, calm, and almost courtly, and he is forthcoming about how he built his book collection, yet averse to using workds like steal or prison or theft. Instead, he "got" books and has been "away" for "doing that."

During our interview, Gilkey smiled politely and nodded in a deferential sort of way. His voice sounded hesitant, which I attributed to the awkwardness and poor acoustics of the prison-booth phones. Later, I would come to view his hesitation as a kind of watchfulness, as though he were playing a role he's not entirely comfortable with: that of a cultured, revered man he has encountered often in books and movies, but hasn't had occasion to study much in person.

One of the only books in his collection that he has read is Lolita, because of its history of controversy. "It was disgusting," he says. Most of what he has collected is fiction, but most of what he reads is nonfiction, either histories or bibliographies or books about collecting books. As a child, his objects of desire, like Sanders's, were comic books, and his favorite was Richie Rich. "But you can never get a sense of completion with that one," he says. "I had 1,500, but there are 2,500 total." He says he was a sensitive boy who asked his mother to walk him to school until the sixth grade. He stole only once back then, a baseball glove from Montgomery Ward, but when he got it home, he realized it was a lefty.

Most of his time was spent at home, playing on his own or hanging around with his father. He occasionally spent time with one or two of his seven siblings, but he didn't play with children in the neighborhood. Instead, he made up his own games. He would line up his comic books on the floor, Richie Rich Cash on one side and Richie Rich Money World on the other, and make them do battle, smashing one comic book against the other. "But then the comics were ruined," he says, "and I wondered why I was doing it. I realized they wouldn't be worth anything."

I had heard that in the past, Gilkey had denied having stolen books, so I assumed he would reiterate his denial. When I picked up the phone to begin our conversation, however, the first thing he said after we introduced ourselves was, "Do you want to know how I got my first book?"

Gilkey explained that he "got" Ira Levin's Rosemary's Baby, Isak Dinesen's Seven Gothic Tales, and an H.P. Lovecraft at the Burbank book fair in 1997 by writing checks from a closed account. The next year, he says he found a receipt on the floor of a hotel and decided to use the credit card number to call in orders for a few things he wanted: a watch, a pizza, and a poster for the movie Psycho. He describes these fraudulent purchases as though they were larks, why-the-hell-not pranks, but the ease with which he pulled them off stuck with him. "It was that easy" is something he says often.

In 1999, Gilkey applied for a job at Saks Fifth Avenue in San Francisco in order to have access to the credit card numbers of wealthy people. He was hired and methodically went about harvesting receipts. "I'd try to get 5 a week, occasionally 10," he says. "Sometimes, they'd put me in a room with a phone and a computer. I wasn't that busy, so I'd research books, then I'd go outside to make calls from a pay phone." He selected his victims from a free ABAA directory he picked up at the Burbank book fair. But it wasn't until 2001 that he says he started collecting seriously.

While Gilkey dabbles in the acquisition of collectibles like crystal, stamps, snuff bottles, and autographs, it is books¡ªor what they signify¡ªthat captivate him. He dreams of building a "grand estate." He says he wants to "feel like royalty, rich, cultured." He would like to be a Victorian gentleman. "I keep visualizing a Sherlock Holmes with a smoking jacket and an old library. I'd have a big antique globe and read next to it." He describes the allure books have for him. "It's a visual thing, the way they look, all lined up on the shelf." The challenge, according to Gilkey, who's spent much of his life alone, is finding people to show the books to. "If you could somehow get visitors over, the first thing you're going to show them is the books. I could say, 'See, look, these are all first editions: this one, this one, this one.'"

One of the most infamous book thieves in recent history is Stephen Blumberg, who stole about 24,000 books from 268 libraries across the country in the '70s and '80s, until he was caught in 1990. When I ask Gilkey if he had ever been tempted to take a book from the library, he says, "That would be stealing." Gilkey says that when he orders books using stolen credit card numbers, "nobody loses really. The cardholder gets paid back, the bookseller gets paid. Course, I'm the big winner 'cause I get the merchandise for free." When I tell Gilkey that some dealers don't carry insurance, and that even when they do, by the time they've paid their deductible, they've still lost money, he says, "If you want to open up a business, you gotta be prepared for stuff like that. Take a liquor store, for example. You're probably gonna get robbed once a month."

Gilkey also doesn't like spending his own money on rare books. "I have a degree in economics," he says. "I figure, the more books I get for free, if I need to sell them, I get 100 percent profit." He is not joking. Gilkey is one of the most diffident, polite people I've met¡ªalways early for mettings, always taking care at restaurants to order less expensive items than I have, always remembering to say thank you. So statements like these are particularly jolting, bringing into sharp and unnerving focus his skewed sense of what is fair and right and reasonable, at least in the world of rare books.

In January 2003, a man identifying himself as Heath Hawkins called Ken Lopez's bookstore in Hadley, Massechusetts. He chatted, decided to order a first edition of Steinbeck's Grapes of Wrath ($7,500), and asked if they could recommend a good place in California to have a clamshell box made for the book. Lopez recognized the content of the conversation more than the voice. Gilkey had called him six months earlier, attempting to order Kesey's One Flew Over the Cuckoo's Nest ($6,500), but the charge had not been approved, and the order was dropped. Lopez had a hunch that this caller just might be the Nor Cal Hotel-Motel Credit Card Thief.

This was the chance Sanders and Lopez had been waiting for. While the caller was still on the phone, Lopez Googled the shipping address. It came up as the Westin hotel in Palo Alto.

After agreeing to send The Grapes of Wrath (a first edition library facsimile¡ª"Our little joke on him," says Sanders) overnight to the hotel, Ken Lopez called Ken Sanders, who called San Jose Police Department detective Ken Munson. The "trilogy of Kens," as Sanders calls them, got to work. Munson, a detective in the high-tech crimes unit, had never worked on a case like this but was eager to give it a shot. He set up surveillance in the hotel parking lot and put two undercover detectives in the lobby, one female, one male, posing as a couple. "We had no idea what we were looking for," Munson said later. "We assumed it was a guy, but it could have been a guy and a gal, two guys¡ªwe didn't know. We had arranged everything the night before, to have somebody behind the desk signal us if anyone asked for the package."

Gilkey showed up, asked for the package, and was handcuffed. He told the detectives he was on his way from San Francisco to a Stanford library to do some research, and that a man on Caltrain had offered to pay him $20 to pick up the book at the hotel. Munson told Gilkey they were going to take the handcuffs off, escort him to the Caltrain station, and hand him the package. "You go meet the guy and point him out to us," he said. On the platform, Gilkey wandered back and forth, walking up to people and making conversation. "I don't know what he was up to," says Munson. Gilkey later told me that one thing he was up to was chewing up a credit card receipt he had in his pocket and, he says, "thinking about running."

When questioned, Gilkey gave the police his name but wouldn't say where he lived. "At the hotel, he'd said he was there to pick up a book for Heather Hawkins, which is the name on the credit card," says Munson. "Later, he said the guy on the train told him to pick up a book for Heath Hawkins. When I asked him about it, I could see the wheels turning. 'Oh yeah," Gilkey says, "maybe the guy told me Heather and Heath Hawkins.' I knew he was lying. Later, it was easy to prove. He had a prepaid phone card in his pocket with only three calls on it. They were all to Ken Lopez."

When the police ran Gilkey's fingerprints, they discovered he was already in the California state penal system; he had been arrested three times for passing bad checks. Munson called Sanders, told him they'd caught the thief, and gave him Gilkey's name. Lane Heldfond, of Heldfond Book Gallery in San Anselmo, was able to correctly identify Gilkey in an online photo lineup, which enabled them to charge him. Shortly thereafter, Gilkey met his $15,000 bail and was released.

For the next couple of months, he went from bookstore to bookstore, first in Los Angeles, and then in the Bay Area, trying to sell a number of books, including several first editions of Winnie-the-Pooh, to raise money for his attorney's fees. The dealers kept in contact with Sanders as Gilkey stopped by their stores. At Gilkey's hearing, when the judge heard what he'd been up to, she set the new bail at $200,000.

While in Los Angeles, Gilkey had left his home address with William Dailey Rare Books. It was for an apartment on Treasure Island, and Sanders assumed it was bogus but notified Munson anyway. On April 22, he got a call from Munson, who said, "I'm in Gilkey's apartment on Treasure Island." The address turned out to be the home Gilkey shared with his father, Walter Gilkey. "There were books on every surface," says Munson. "On counters, in closets, in the bedrooms, on the dining table, the dining chairs, the floor." Some were covered in bubble wrap. "It was haphazard, but it looked like he took care of them," says Munson. "You could tell he had a love for these things."

Munson asked Sanders to give him the names of any books he was sure were stolen.

"Is there an On the Road by Jack Jerouac?" Sanders asked.

"Yes," said Munson.

"Grab it!" said Sanders. "What about a Mayor of Casterbridge?"

"Yes."

"And Lord Jim?"

"Yes."

And so it went. With Sanders's help, Munson was able to identify 26 stolen books in Gilkey's apartment. But with no futher proof of theft, the majority of books were left behind. Sanders says that to this day he's plagued by the thought that if he had been able to provide Munson with more information, more books could have been saved.

Some of Sanders's fellow dealers have told him he is exaggerating when he estimates that Gilkey stole $80,000 to $100,000 worth of books before he was put behind bars. But Gilkey told me that during one four-month period in 2001, he "spent" around $200,000, mostly on books. But perhaps as significant as the still-unknown number of books he stole or their value is the way his deceptions helped to change the trade. Dealers are now far more vigilant when taking orders, securing more information from buyers and confirming with credit card companies that the shipping address matches the cardholder's billing address. They are now warier, less trusting.

Gilkey served about half of his three-year sentence and was released from Deuel Vocational Institution in July 2005. He was paroled in San Francisco and carries a notepad with a list of what to do each day. These lists almost always include rare book research at the library and visits to legal advisers to check on the feasibility of one of the many lawsuits he is interested in filing.

He is a curious man with an energetic mind, and he is full of ideas. He would like to collect a first edition of each of the Modern Library's 100 Best Novels, although he realizes that the prices near the top are astronomical, so he's starting at number 100, The Magnificent Ambersons by Booth Tarkington. He wants to make a documentary film about how he searches for famous people's autographs in unexpected places, such as school yearbooks. He has written a 100-page homage to John Kendrick Bangs, an obscure late-19th-century American writer whose signature work involves fantasies set in the afterlife. He also plans to write a book about "a guy who gets recruited by the government ot be a spy to look for missing rare books."

Gilkey spends his days visiting bookstores, doing research at the library, and walking around Union Square, where he likes looking in the shops. When I ask if I can tag along with him on a trip to a bookstore, Gilkey agrees an, to my disbelief, suggests that we visit Brick Row. Then he hesitates. "Maybe they'll recognize me," he says. But he reconsiders, thinking it won't be a problem.

It is.

On September 12, 2005, Gilkey and I walk into Brick Row. Located near Union Square, it is on the second floor of a building that houses several art galleries. I can see why he favors this shop. If you were to ignore the computer and phone on Crichton's heavy wooden desk, you could imagine yourself in a 19th-century bookshop or in the opening scene of a Masterpiece Theatre episode. Majestic-looking, leather-bound books sit in cases along every wall and on a graceful arc of shelves that runs through the middle of the shop. It smells of history and knowledge and privilege, an intoxicating blend for someone like Gilkey.

As soon as Crichton looks up from his desk, he suspects who is standing before him. The tension is as thick as an Oxford English Dictionary, yet it seems not to bother Gilkey in the least. (When I met with Crichton later, he told me he had decided not to make a scene or throw Gilkey out because he did not know who I was or if I knew about Gilkey's past.) Gilkey asks Crichton if we can look around. Crichton mumbles something, turns his back to us for a moment, and then turns to face Gilkey. "What's your name?"

"John."

"John what?"

"Gilkey."

Crichton pauses a moment and walks toward his desk. He turns back around and watches intently as Gilkey points to various books and whispers, instructing me about the authors he might be interested in: Nabokov, D.H. Lawrence, Willa Cather. He tells me he stays away from bibles. Pointing to his list of the Modern Library's 100 Best Novels, he further explains how he goes about looking for books. He asks Crichton if they have anything by Nathaniel Hawthorne. Crichton answers firmly, "No."

Then, in a show of astounding hubris, Gilkey tells me, in a slightly louder voice, an improbable story about how at age 8 or 9 he bought his first rare book, a first edition of William Saroyan's The Human Comedy, published in 1943, for $60. Given the circumstances, it is excruciating to listen to. "And what happend was, they actually cheated me. I found out six or seven years ago that it wasn't a first edition, first printing, which is how they sold it." He tells other tales, one about buying a $3,500 book that was supposed to have been sent with a dust jacket but wasn't, dropping its value by 50 percent. In an even louder voice, he describes buying books at book fairs, only to discover later that he'd been ripped off.

Later, I ask Gilkey if he had told those stories for Crichton's benefit, and he admits that he had. "Those book dealers have more fraud in their business than I ever committed," he says. "What goes around comes around. I was just evening things out."

After that, each time I spoke with Gilkey, he was more incensed at the inequities between the haves (rare book dealers) and the have-nots (collectors, like himself, "who are not multimillionaires"), and more strident in his justification of what he has done. "I could have got much more," Gilkey has said numerous times, as though in defense of what he sees as a collection that's not big enough. "I could have, if I hadn't been working."

He won't say where his unrecovered books are stashed, but fondly recounts what it is like to hold one of this ill-gotten treasures. "Strangely enough, it's like a bottle of wine. I kinda smell the newness of the books, and I feel the crispness of it, see how it is, make sure there's nothing wrong with it, open it up very gently, thumb through a few things. I think about whether I want it signed. Then I put it up in a plastic container. I'm thinking that maybe 30 years later, this book could be worth something. I don't want to make any mistakes. That's what I think. Preserve the book."

Late last September, Gilkey walked into Acorn Books on Polk Street and was recognized. The man at the store asked him to leave, which Gilkey found absurd. "It's hard for them to figure what's in my mind," he says. "I was just going in there looking for a bibliography. I was actually going to pay for something." He also thinks that ordering him out of the store may have been a civil rights violation, and he intends to add that bookseller to the list of people he may sue. For the first time since I started meeting with Gilkey, he seems dispirited and speaks in a resigned tone of voice.

"I probably won't be able to go into any bookstores around here anymore," he says "Not in San Francisco."

Postscript: After this story was written, Gilkey was arrested for violating parole after he attempted to sell stolen items on eBay, and was sentenced to three and a half months in prison. He is expected to be released this month.