Gabby St. Claire Thomas and her Cold Case Squad reunite to solve a missing person's case. A friend of Gabby's husband needs help. His wife, Brooke, went to work one day and never returned home. No one has seen or heard from the woman in four months, and every lead has dried up. Gabby and her team begin to unravel clues about Brooke's life . . . and not all is as it seems. With each new layer that's revealed, they realize the case may be bigger than they ever imagined. Did Brooke walk away from her life . . . or did she become ensnared in something deadly? Gabby fears this investigation won't be the clean sweep she hoped for. No, the dirt she's turning up might be more of a toxic stain. But as the stakes become clear, she realizes that failure isn't an option.