When the body of a childhood friend turns up in the Narrows of Zion National Park, Emmeline Helliwell, a special agent with the National Park Service, is called in to investigate the murder. Grief-stricken over her mother’s recent death, Emme had hoped to turn in her badge for a quieter life, but the case is too personal for her to turn down. The investigation turns treacherous as bodies pile up. Emme knows she has to track down the killer before they take more lives.