Cold cases haunt the present in the desert city of Phoenix, Arizona. 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... CONCRETE DESERT: In 1959 a young woman took a late-night cab home and disappeared. Two weeks later, she was found naked, strangled in the Harquahala desert. Mapstone links her death to four other girls similarly strangled, stripped and dumped. Were these deaths the work of a serial killer? Mapstone's research is interrupted by his reacquaintance with an old flame. Back then, it ended badly, but now she wants him to find her sister who has disappeared. Initially, Mapstone has more leads on the 40-year-old murders than the missing sister. Until she's found in the desert. Stripped. And strangled.