Wire in the Blood - Season 6 (2008)

Tony attends a conference of psychologists, where he is a guest speaker and where he meets an old friend Rachel White, another delegate. He has drinks with her in her room but leaves before having sex. Next morning she is found dead and he was the last person to see her alive, marking him as a suspect. Then another psychologist is also murdered whilst Alex investigates a serial killer whose targets are prostitutes.

Tony is allowed to assist in the investigations. He sees the murders as ritualistic as 'Power Not Truth' was written in the dead doctors' blood. He also begins to see a connection with the murders of the prostitutes and, against Alex's advice, offers himself as bait to trap the killer.

Two young men are found murdered, the only connection being that skin from one of them is found under the other's fingernails. As other bodies are found, Tony deduces that a sadistic gay murderer is abducting white boys and forcing them to kill each other. Meanwhile Michael Bryant, the cannibal killer whom Tony helped to put away, sends him a message from the secure unit where he is incarcerated, telling Tony that he is planning to escape and will see him soon.

An Asian man is killed but the pattern is different to the serial killings of the white boys which appears to have stopped. However, Ellie, a young widow, is abducted and, in the search to find her, Tony looks for comparisons with the other murders. Bryant, claiming that he has found God, asks for an audience with the secure unit's chaplain, whom he then kills, making his escape in the chaplain's robes.

Another serial killer is at work. This one kills homeless men by stabbing them through the heart but a bizarre ritual is also at work because the bodies are bathed and wrapped up in paper before they are left around the town's business area. Alex is called away and her place taken by the young Oxbridge graduate Hall,of whom Tony is initially suspicious but he turns out to have a psychology degree and to be a big fan of Tony's work. A more sinister fan,clearly Bryant,is leaving 'presents' on Tony's door-step.

When the woman area mental health commissioner is murdered - with Bryant the culprit - Tony is given police protection and sergeant Kevin Jeffries moves in with him. At the same time he is trying to unravel the mystery of the murdered homeless men and discovers that not all of them are what they first appear to be. His work and life, however, will inevitably be interrupted by Bryant, leading to their final show-down.