Detectives Ally Emerson and Kate Snow have barely recovered from the traumatic hostage ordeal that nearly cost them everything in the Peterson case-when they're pulled straight back in.A call from their superior, DI Adam Benson, leads them to a grim discovery: a new body, freshly buried in the grave of a previous victim. The timing is chilling. The message is deliberate. And one thing is certain-John Peterson is no longer the culprit.So, who is?All signs point to Annabel Arran-Peterson's unstable and dangerously unpredictable daughter. After holding Emerson captive for forty-eight terrifying hours, they know exactly what she's capable of. What they don't know is how far she's willing to go-or how quickly she's escalating.As the investigation intensifies, another threat emerges from the shadows. DI Benson is being blackmailed. Explicit photographs threaten to expose his private life, and the anonymous sender is closing in. With his career-and personal life-on the line, the stakes couldn't be higher.Now Emerson and Snow must race against time to track down a killer growing bolder by the day, while protecting their boss from a scandal that could destroy him.Amid the chaos, their own lives refuse to stand still. Their relationship deepens, offering rare moments of light in the darkness-and the promise of a future they're only just beginning to build, complete with a new home and their loyal dog, Ziggy.But with danger closing in from all sides, can they finally bring the Peterson case to an end… or will the past claim one last victim?Find out in Sanctuary.