by Peter Heller chronicles the life of a Yellowstone National Park ranger, Ren Hopper. Living a solitary life in a remote cabin, Ren spends most of his time-saving tourists from dangerous wild animals and going after drunk or reckless drivers. But, his job snaps into clearer focus when he begins to track a new predator: the human responsible for tracking down and killing Yellowstone’s wolf population. Things get more personal when Ren’s friend Hilly, a wolf biologist, gets caught in a trap that seems to have been set deliberately. Ren and Hilly’s investigation leads them to encounter poachers, shadowy ranchers, and a potential land grab scheme that’s turning dark.