Two young men are tricked by their girlfriends into stripping themselves nude for a midnight swim, during which the girls run off with the boys' clothes, leaving them to streak through Denton. One is arrested but the other, Roman Cassell, gets back to his office where,the next day ,he is found beaten to death. Suspicion falls on Jason Cohu and his father-in-law Joshua Ray, who blame Cassell for the death of Jason's wife and were in the vicinity of the office that night. Joshua admits to the murder but Frost believes he is innocent, misguidedly protecting his son-in-law and CCTV footage proves him right. At the same time Carl Meyer is released from a twenty year prison term. When he was a young boy he was accused of murdering a little girl with whom he used to play and with whose corpse he was found. Her cousin disappeared on the same day and he was also accused of killing her. The girls' family conduct a vendetta against him to which he shows no malice, claiming, as he had done all along, that he is innocent of both deaths. His only ally is the local vicar, whom Frost initially dismisses as a liberal 'do-gooder'. However she successfully convinces Frost that a simple lad like Carl would not be devious enough to maintain the same deception for so long unless he was indeed not guilty. This means that the real murderer is still at large.
—don @ minifie-1