As a Fish and Wildlife police officer, Luke McCain and his partner - a yellow Lab named Jack - spend their days patrolling the rivers, lakes, and forests of the wild and scenic Cascade Mountains in Eastern Washington. After hunters discover human remains inside a bear's stomach, McCain is thrust into the investigation. As more dead women are found in McCain's region, authorities suspect a serial killer is prowling the mountains he knows best. McCain will need his knowledge as an outdoorsman, and his instincts as an investigator, to track the psychopathic predator.

Dela Alvaro is a disabled veteran who grew up on the Confederated Tribes of the Umatilla Reservation. When an IED in Iraq ended her military career, she came home to reassess her life and landed a job in security at the Indian run casino on the reservation. Not even a year into being the assistant to the head of security, Dela is promoted on a trial basis. When one of the casino employees is found stabbed and stuffed in a laundry chute, she knows she can kiss head of security goodbye if she doesn’t find the killer before the media gets hold of the story.

The ancient Indian art of tracking is his greatest strength...and also his biggest weakness. Fish and wildlife state trooper Gabriel Hawke believes he’s chasing poachers. However, he comes upon a wildlife biologist standing over a body that is wearing a wolf-tracking collar. He uses master tracker skills taught to him by his Nez Perce grandfather to follow clues on the mountain. Paper trails and the whisper of rumors in the rural community where he works draws Hawke to a conclusion that he finds bitter.

Fish and Wildlife State Trooper Gabriel Hawke's job is to find a missing family in the Eagle Cap Wilderness. After finding the parents murdered, can he find a little girl on the run? Hawke is an expert tracker, but he isn’t the only one looking for the child. Even leaving the mountain, the girl isn’t safe. The murderers are looking for something - something they believe the child possesses.

Harney County, Oregon, 1968: Nick Drake has a chest full of medals and enough demons to fill a duffel bag. He's been trained to kill but was never retrained to rejoin society. Drake flees to the lonesome high desert in search of redemption and takes a job patrolling wildlife refuges where the only conflicts are keeping out stray cows and ticketing poachers. But then he stumbles across a girl's body ritually placed in a gully. Her murder is only the beginning, and Drake must face humanity's heart of darkness once again if he's to stop a killer from turning even more gullies into graves.