In the run-up to a multi-faith conference, a figure masquerading as a warrior monk is murdering the religious leaders who have gathered in the city. The way each killing is carefully staged leaves criminal profiler Fiona Nightingale certain that a religious fanatic is on the loose. In the search for the killer, three individuals come under suspicion: a vicar who has lost his faith; a student who has suffered a miserable childhood at the hands of his God-fearing father; and an attention-seeking young actress. Now Nightingale must race against time to uncover the real ringleader—before it is too late.