Mark Treasure has no idea that accompanying his actress wife on location to a picturesque West Country town could possibly lead to murder.

The merchant banker is asked by Chiversley's Area Bishop to become involved in the financial affairs of the local covent - one with only three nuns left in residence and assets worth eleven million pounds. But this simple challenge develops into a double murder mystery when it becomes clear that one of the people already responsible for managing the convent finances has died in suspicious circumstances, and when a second is found half-naked and strangled soon after leaving an important dinner party. And what of a callous arson attack on the convent itself?

Convinced that the police are about to arrest the wrong suspect, Treasure must use all his experience and ingenuity to uncover important evidence and unravel a complex web of deception. But time is against him and a killer is on the loose.