In 2012, a New York auction catalogue boasted an unusual offering: "a superb Tyrannosaurus skeleton." In fact, Lot 49135 consisted of a nearly complete T. bataar, a close cousin to the most famous animal that ever lived. The fossils now on display in a Manhattan event space had been unearthed in Mongolia, more than 6,000 miles away. At eight-feet high and 24 feet long, the specimen was spectacular, and when the gavel sounded the winning bid was over $1 million. Eric Prokopi, a thirty-eight-year-old Floridian, was the man who had brought this extraordinary skeleton to market. A onetime swimmer who spent his teenage years diving for shark teeth, Prokopi's singular obsession with fossils fueled a thriving business hunting, preparing, and selling specimens, to clients ranging from natural history museums to avid private collectors like actor Leonardo DiCaprio. But there was a problem. This time, facing financial strain, had Prokopi gone too far? As the T. bataar went to auction, a network of paleontologists alerted the government of Mongolia to the eye-catching lot. As an international custody battle ensued, Prokopi watched as his own world unraveled. This is a stunning work of narrative journalism about humans' relationship with natural history and a seemingly intractable conflict between science and commerce. A story that stretches from Florida's Land O' Lakes to the Gobi Desert, it illuminates the history of fossil collecting--a murky, sometimes risky business, populated by eccentrics and obsessives, where the lines between poacher and hunter, collector and smuggler, enthusiast and opportunist, can easily blur.