Outwardly a respectable young family man and Belfast psychotherapist, in reality Paul Spector is the dangerous stalker of lawyer Sarah Kay, breaking into her flat and stealing her undies. The police are called but fail to persuade Sarah to move out. At the same time local officer Jim Burns calls in his English colleague Superintendent Stella Gibson to assist in solving the murder of architect Alice Monroe. Stella sees links between Alice's slaying and that of Fiona Gallagher and suspects a serial killer though not everybody takes her seriously. On the night that the police are called out to discover a cache of weapons in a car Spector, telling his wife that he is going to do voluntary work, kills Sarah Kay with police officers outside her house and unable to get in. Written by don @ minifie-1

Having killed Sarah, Spector ritually bathes her and paints her nails, snips off a lock of her hair and takes a necklace. Later he masturbates over film he has taken of her corpse. Stella refuses to speak to local reporter Ned Callan as to her involvement in the Monroe case. Afterwards, she has meaningless sex with young police sergeant James Olson. Next day she is angry to see that Callan has written an article about her arrival in Belfast. She is then called out to the murder scene of Sarah and asks to take over the investigation. She learns from the pathologist that Sarah was pregnant. Spector's wife's teen-aged baby-sitter comes to the house to download music and tries to steal the lock of Sarah's hair. Spector man-handles her to get it back, claiming it belonged to his mother though she is suspicious. At the same time the murder of drug-dealer Michael Lockwood seems to spark off a retaliatory murder. Written by don @ minifie-1

Stella learns from ACC Burns that the new victim is Jimmy Olson. She confesses to having had sex with him, unaware that he was married, and is advised by Burns to arm herself. Rob Breedlove, who runs a brothel in which Alice's widower Aaron has an interest, is also perturbed by Jimmy's death. Stella holds a briefing to alert her officers to the fact that they are dealing with a serial killer, who is addicted to his crimes. She gives a press conference at which Ned Callan poses awkward questions, before selecting her team and giving an accurate profile of the murderer. Spector goes with his wife and children to visit her parents but makes a point of studying Stella on her television appeal. His mother-in-law is suspicious of the fact that he has given his little daughter Olivia a necklace, the one stolen from Sarah, whilst Olivia tells her mother Sally Ann that she knows of a scrapbook in which her father keeps a perverted log, detailing his crimes. Soon afterwards Spector selects his ... Written by don @ minifie-1

DCI Eastwood tells Burns that he took a call on Olson's phone which was made at a hotel by rogue cop Rob Breedlove, whom they link to Aaron Monroe, his businessman father Morgan and a prostitution racket. When quizzed about it Breedlove kills himself but Burns confronts Morgan Monroe with his findings. Spector is censured by his boss for making an impromptu and empathetic house call to his client Liz Tyler, a battered wife whose husband James has complained about him. However Spector ensures that Liz goes to a refuge whilst arranging for her husband's arrest. Spector sends a bizarre, anonymous letter to Sarah Kay's father, claiming he would not have killed her if he had known she was pregnant. Stella believes it is less a case of remorse than annoyance that his 'perfect' murder was tainted but allows Mr Kay to make a public appeal nonetheless. A friend of pathologist Reed Smith comes forward and tells Stella she once met a one night stand whom she knew only as Peter who tried to ... Written by don @ minifie-1

Spector is frustrated and angry for he has failed in his perfect murder, killing Jack Brawley whilst Annie Brawley survives and is taken to hospital, where Stella tests for DNA on her body. Spector's wife Sally Ann sees him on CCTV footage of Sarah Kay's last recorded movements and makes him go to the police station to eliminate himself from enquiries. Sally Ann covers for him but is angry when he lies about his nocturnal jaunts by admitting to an affair with the under-age baby sitter. Sally Ann leaves him but he wins her back. After an Identikit picture of 'Peter' is published and Sarah's father makes an appeal Stella receives a bizarre phone call from Spector, promising to end his killing spree, though that is not the end of the matter. Meanwhile Eastwood accuses Burns of weakness for tipping off the Monroes that he knows about their illegal activities, allowing Aaron to flee from the law. Written by don @ minifie-1