Three years after the events of Past Lies, Amy Devlin, in her final days in Beverly Hills' Cold Case Division, uncovers a series of murders that seem connected through time. Every 10 years, a sinner with a saint's name has been brutally murdered on All Saints Day. With a string of cases spanning 30 years, and another killing likely to occur within the month, can Amy convince anyone these unsolved crimes are connected? And when she starts digging, will she make herself the next victim?