Pub landlord Roly Henderson is accused of stabbing to death his wife Joanne in her sleep and cutting off her little finger. DI Kate Warren is anxious to convict,under pressure from her father a deputy chief constable,to further her career but Clarissa and Nikki find proof of Roly's innocence and his little daughter Emma recalls seeing a strange man in the pub. Nikki visits Simon Marshall,convicted of killing his wife Eleanor four years earlier as her finger was also chopped off after death. Simon tells Nikki his wife was murdered by a biker and Nikki and Jack find evidence to support his story. Nikki believes this man killed Joanne,Eleanor and a third victim,Imogen Lane,who married the older policeman Alan who rescued her from her pimp when she was a teen-aged prostitute. Alan was convicted of his wife's death but is now released. Imogen's mother Edith hated Alaan,believing he killed her husband as well as her daughter,whom she feared he would harm. Edith is unaware that she is being shadowed by Janice Masters,a single parent who also has a little finger missing.

Jack discovers that Kate,under pressure from her corrupt father,has tampered with evidence to incriminate Roly Henderson and demands she accept Nikki's opinion that Alan Lane killed all three victims. They visit Anne Percival,the retired officer who sent lane down even though Imogen's body was never found - in the event because,thanks to Anne,she was given a new identity as Janice Masters. Nikki finds out that Lane has killed nine women who all has histories of domestic turbulence so that their husbands were blamed. After Anne has fatally tried searching Lane's house the team must stop him before he can get to Janice.

Kevin McDowd, a boy with behavioural problems, is restrained from escaping Kingscote Bows, his residential care home whilst, a few miles away, his mother Jackie dies in a car crash, having ingested an excess of anti-depressant pills. Nikki believes she was unlawfully killed and evidence points to Kevin being the culprit. Kevin goes on the run with fellow resident Serena, who, to the horror of care assistant Tilly Maddox, is being sexually abused by deputy manager Conor Flannery, but they are cornered by the police with unfortunate results.

Examining Kevin's corpse Nikki is puzzled by stun marks on the body and the fact that Jackie had set up a camera in his room. Thomas is also curious regarding two other mysterious deaths, one at Kingscote Bows, the other at the Pleasant Manor care home, where both were regularly visited by Dr Kahari. When Serena goes missing and Tilly is found dead after threatening to expose Flannery Clarissa books herself into Pleasant Manor to investigate herself,. She unmasks the killers but needs to be rescued by Jack when she puts herself I danger.