In 1876, two monomaniacal paleontologists pillage the Wild West, hunting for dinosaur fossils, while surveilling, deceiving and sabotaging each other in a rivalry that will come to be known as the Bone Wars. Into this treacherous territory plunges the arrogant and entitled William Johnson, a Yale student who has joined world-renowned paleontologist Othniel Charles Marsh on his latest expedition. But when the paranoid and secretive Marsh becomes convinced that William is spying for his nemesis, Edwin Drinker Cope, he abandons him in Cheyenne, Wyoming, a locus of crime and vice. William is forced to join forces with Cope and soon stumbles upon a discovery of historic proportions.