When Jen, the largest, most complete Tyrannosaurus rex skeleton ever found, surfaces in Sherriff Walt Longmire’s jurisdiction, it appears to be a windfall for the High Plains Dinosaur Museum --- until Danny Lone Elk, the Cheyenne rancher on whose property the remains were discovered, turns up dead. With millions of dollars at stake, a number of groups step forward to claim her, including Danny’s family, the tribe and the federal government. Walt is determined to find out who would benefit from Danny’s death.