In the affluent, historic town of Ludlow, a teenage boy dies in a fall from the castle ruins. Accident or suicide? No great mystery, so why does the boy’s uncle, newly-retired detective sergeant Andy Mumford take his personal fears to diocesan exorcist Merrily Watkins?

More people will die before Merrily, her own future uncertain, uncovers in those shadowed, medieval streets, a dangerous obsession with suicide, the nature of death and the afterlife.