London, Autumn 1882. When the World’s End Investigation Bureau receives an anxious visit from a trio of elderly siblings, Lily Raynor and Felix Wilbraham realise that Alethea, Thomas and Frances Fetterplace are keeping back the heart of the matter. Ancient bones have been uncovered in their garden, and they believe they know whose they are. But so, it appears, does someone else.

A visit to the secretive old Fetterplace house tucked away behind Tower Hill proves frustrating, for the distressed siblings will not permit an inspection of what lies in their rose bed. Overcoming his own and Lily’s strange reluctance, Felix returns by night . . . and discovers that the Fetterplace siblings have good reason for their fear.

Unconscious and gravely injured, Felix is brought back to Lily’s door by concerned strangers. Fully occupied with trying to save his life, Lily begins to wonder who attacked him, and what convinced this brutal assailant that he must die.

Who is buried in the makeshift grave? Did Felix discover something sinister alongside the bones? Whatever it was, it must be dangerous indeed if keeping it secret requires taking a life . . .