A PHOENIX COLD CASE: David Mapstone has returned to Phoenix, Arizona, the desert city he left behind a lifetime ago. The ex-cop, ex-history professor is working the police dept’s cold case desk, unearthing long-buried secrets. And he’s good at it: as an ex-historian Mapstone knows the past is never past, as an ex-cop he knows he can’t trust anybody… CAMELBACK FALLS: When his friend Peralta, newly sworn in as sheriff, is shot by a sniper, Mapstone can’t keep a cool, academic distance. And he’d better not: while Peralta lies comatose in the hospital, Mapstone is appointed acting sheriff. As he struggles to make sense of this unwanted promotion, Mapstone must unravel the meaning of a cryptic note scrawled by Peralta before the shooting. The note simply reads: Camelback Falls. To decipher the message, Mapstone will have to confront his own past and the deadly consequences of a small-town shoot-out in 1979 that left he and Peralta standing over four dead bodies. For Mapstone, the past has never been so deadly.