The man who tried to kill Deputy Mattie Cobb and may have killed her father thirty years earlier. But when Mattie reaches the Colorado state prison where she'll finally get to interview him, he's dead in his cell. There's only one clue: a map leading to Timber Creek and rugged Redstone Ridge. Left to explore the map's clue without her usual partner Cole Walker, Mattie and her K-9 Robo journey into the burned forest surrounding Redstone Ridge, where they're called to help investigate the death of a young woman found in a campground. Then Cole goes missing, stranded alone in the high country with a person that Mattie now suspects is the mastermind behind several murders, including her father's.