Collectors are elusive subjects. They describe their obsessions like a genetic inheritance or a contagious disease—something that chose them—which doesn’t help outsiders understand their urge to amass. Baseball card mavens sometimes talk about trying to reclaim their childhood, but fortunately, in the thin but far-ranging The Card, the pursuit of old scraps of cardboard is easier to comprehend. Old baseball cards are simply valuable, no mawkish tales required. In what aficionados call “the hobby,” nothing is more storied or expensive than the 1909 Honus Wagner card showing the ruddy batsman looking uncomfortable in a Pittsburg [sic] Pirates jersey buttoned up to his Adam’s apple. Wagner famously stopped the printing—one legend has it that he objected to using his name to sell tobacco—making the card a wildly expensive souvenir of baseball’s early modern era. Of the 50 or so surviving specimens, most are in poor condition. The flimsy apex of them is high quality and was once owned by Wayne Gretzky; it sold for more than $2 million in February. (The sale came off despite credible speculation that the card has been “trimmed,” meaning it was cut out of a sheet of cards, a practice that would normally devalue a card.) The history of baseball cards can be divided into two main chapters. First, there was a time when they were worth nothing. Then their owners grew up. Michael O’Keeffe and Teri Thompson of the New York Daily News’ investigative sports team write about the early days of baseball and sketch an admiring portrait of Wagner, aka the Flying Dutchman, a nice enough guy and among the top players of his time. A crack shortstop with a lifetime .329 batting average, he was one of the first five inductees to the hall of fame. However, their red meat is the charlatans and chumps who have crossed the card’s path since. Of the former owners, the most intriguing is Michael Gidwitz, a wealthy Chicago collector whose minimalist apartment houses a world-class collection of Alfred E. Neuman paraphernalia. Gidwitz is both charming and disingenuous: After becoming the first person to sell a baseball card—the card—for more than $1 million, he distanced himself from the hobby for its shady practices. The authors jump on auction houses paying shills to raise bids and card appraisers who have a more forgiving eye for their best clients’ material. Other memorable characters are John Cobb and Ray Edwards, two black men who quixotically spend years trying to prove to the insular and white card-­collecting world that their Wagner is authentic, though it may not be. The book also dives into the less appealing aspects of the baseball memorabilia business. Baseball cards can be “doctored”—corners sharpened, colors brightened. The memorabilia trade is even more absurd. A mass-produced item such as a bat or a glove derives value from being used by a great player or during a memorable moment; Mark McGwire’s 70th home-run ball of 1998 sold for seven figures. When trying to prove the provenance of a 40-year-old baseball, the potential for abuse is as limitless as the number of suckers out there. O’Keeffe and Thompson have written an engaging book about an American artifact, but The Card’s most important legacy may be further draining the credibility of a silly hobby. Sports fans and general readers will find plenty to enjoy. Anyone who doesn’t might have a card to sell you.