When a drought drains the local Thornfield Reservoir, uncovering a long-drowned small village and the skeleton of a murder victim from the 1940s, Detective Alan Banks and Detective Sergeant Annie Cabot are called in to investigate.

It's an incendiary moment for St Oswald's school. For the first time in its history, a headmistress is in power, the gates opening to girls. Rebecca Buckfast has spilled blood to reach this position. As the new regime takes on the old guard, the ground shifts. And with it, the remains of a body are discovered. Rebecca will bury the past so deep it will evade even her own memory, just like she has done before.