A Catholic father-of-four is arrested after a prostitute is found murdered, but he denies the crime. Beck returns from sick leave to work alongside Penhaligon, who is privately convinced that Beck raped her but has no forensic evidence. While Fitz faces a family tragedy, a second prostitute is attacked while the chief suspect is still in custody.

An identical murder takes place while David Harvey is in custody. Fitz visits his priest brother Michael and accuses him of murder, while Maggie Harvey demands that her husband is released.

After another prostitute is slain, Fitz comes to believe that David Harvey's wife Maggie is the killer, in spite of vehement protesting by the police and his brother, Father Michael.

Bill Nash smiles at Stuart Grady, and, in those few seconds, changes the course of their lives and inadvertently turns them both to murder. Meanwhile, on the domestic front, Judith finally rebels.

Fitz is pitched against Grady and Nash, whose relationship is now spinning dangerously out of control.

Fitz privately advises a patient who seems to be having problems with her husband. Fitz's advice, for which he charges her £50, leads her to conclude that she should leave him.

Fitz is asking DCI Wise to replace him with Irene as the killer may stop killing if she realises she is not getting the shrink's undivided attention. Irene agrees to change, but finds the nature of the job, and the pictures of her dead students too much to stomach and goes missing.