During a routine patrol along the Yakima River, Washington Department of Fish and Wildlife officer Luke McCain encounters a terrified young woman fleeing a man she believes killed two people in a homeless camp in Seattle. Her story convinces Luke to contact his wife, FBI Special Agent Sara McCain, who goes to work with Seattle Police to identify and locate the killer before he finds the woman and makes the potential witness his next victim.
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Meanwhile, Luke uncovers a group illegally excavating prehistoric mammoth bones on state land. As he and his dog Jack confront the armed diggers, Sara’s case reveals a chilling link between a possible serial killer and the witness’s shadowy pursuer. Their investigations collide in the foothills of the Cascade Mountains, where Luke and Sara must stop a calculating killer and expose greed-driven criminals threatening history itself.
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