A John Doe is found months after his death; an attractive female agent for a championship athlete is believed to have jumped to her death from a rooftop. Forensic pathologists must sort out time and methods of death.

Sam Ryan steals a toothbrush to get the DNA of the father of the unborn child of a suspected suicide. Tangled relationships between an athlete and his family are amplified when his body is found hanging in her apartment. Police arrest the athlete's brother-in-law after an anonymous tip. Harry's attempts at determining time of death by the growth of maggots give a wrong answer.

Carmody goes on the run and Danielle is killed. The same man's DNA is found in her flat as on Ruth's corpse. Leo's partner Janet persuades him that Neill is not dishonest and Neill discovers that Carmody is a car salesman working with Webb. A failed police college entrant some years ago, he has persuaded his wife and mother - as well as Ruth,Danielle and Webb - he is an undercover cop though when Janet interviews his mother she says that he was a fantasist since childhood. Clearly he is a loose cannon, rubbing out those who discover his secret and must be found. Harry discovers that his father was a bully, driving his mother to having an affair.