A gripping narrative of a fearless paleontologist, the founding of America's most loved museums, and the race to find the largest dinosaurs on record.

In the dust of the Gilded Age Bone Wars, two vastly different men emerge with a mission to fill the empty halls of New York's struggling American Museum of Natural History: Henry Fairfield Osborn, a privileged socialite whose reputation rests on the museum's success, and intrepid Kansas-born fossil hunter Barnum Brown.

When Brown unearths the first Tyrannosaurus Rex fossils in the Montana wilderness, forever changing the world of paleontology, Osborn sees a path to save his museum from irrelevancy. With four-foot-long jaws capable of crushing the bones of its prey and hips that powered the animal to run at speeds of 25 miles per hour, the T. Rex suggests a prehistoric ecosystem more complex than anyone imagined. As the public turns out in droves to cower before this bone-chilling giant of the past...