Schoolgirl Joanna Barnes, a member of a religious cult, is discovered to be having an affair with the married leader of the group, Kenneth Trant.

When confronted about it, he and the other leaders abduct her and the police reluctantly call in criminal psychologist Fitz to help find her.

When Trant's wife and sister discover that Joanna is pregnant they embark upon a vendetta against her that ends in attempted murder.

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.