Case Sensitive premieres tonight on ITV1

The bodies of Geraldine Bretherick and her 5yr old daughter Lucy are discovered in the bath at their home by Geraldine’s best friend Cordy O’Hara and her daughter Oonagh. An apparent suicide. But, do Cordy and Oonagh know more about Geraldine and Lucy’s deaths then they are letting on? DS Charlie Zailer arrives on the scene. DS Simon Waterhouse is already there. Charlie and Simon are uncomfortable with each other, a sense that they are both on edge. Geraldine’s wounds look self inflicted and there is a suicide note. Did she kill her child before killing herself? Geraldine’s husband Mark tells Charlie and Simon that he was away on business in Switzerland when it happened, but insists there’s no reason he can think of that she’d do this. They were happy and everything was fine.

Sally Thorne is watching a news report on the story at home, with her husband and two children. She’s sent reeling when she hears the name Mark Bretherick and then sees a photograph of Geraldine and Lucy. The next morning, she arrives at the hotel where she works. She tells her colleague and best friend, Esther Taylor that she had a one night stand with the husband from the news story – Mark Bretherick. Esther warns Sally against trying to contact him again but she’s keen to let him know that she’s thinking of him.

Sellers (CID) finds diary entries written by Geraldine on Mark Bretherick’s laptop, seemingly expressing her unhappiness with being a mother. Charlie seeks advice from the criminologist Prof Harbord and his assistant, Jonathan Hey. They suspect that Geraldine killed Lucy and herself as an act of revenge against Mark Bretherick. What could he have done wrong? Charlie visits Cordy who insists Geraldine was happy and would never hurt Lucy. Cordy – not Mark’s biggest fan – tells Charlie he could be very possessive. Charlie wades through a copy of Harbord’s book about killing in the family, ever more convinced that their theory is correct. However, the next morning, her bubble is burst by Simon – who admits that he went to meet Mark’s PA and has discovered that he had a first wife who died in a drowning accident. Also, that his alibi is shaky – Simon is convinced that Mark merits further investigation

Sally drives out to Cornmill House to see Mark Bretherick. She realises that this isn’t her Mark Bretherick and he, in turn is horrified to discover that there must be a man out there pretending to be him. Sally insists that he talked about Geraldine and Lucy and knew intimate details about their lives. She spots a photo of Geraldine and Lucy– the same photo she was shown by her ‘Mark’. She recounts her meeting with the man but is then terrified when Mark insists that she comes to the police with him; she has to tell them what she’s told him. He demands to know her name and, panicked, she tells him that her name is ‘Esther Taylor’ and when he’s out of the room, she flees to her car, taking the photograph of Geraldine and Lucy with her.

Back at work, Sally tells Esther what happened and shows her the photo of Geraldine and Lucy. Taking it out of the frame, they discover that the photo conceals a second picture, it’s of another woman and little girl, taken in the same spot. Who are they? Back at the station, Charlie and Simon are discussing Mark Bretherick’s possible involvement with Harbord, Hey and Proust when Mark himself arrives, furious that there is a man out there ‘pretending to be me’. He tells them about ‘Esther Taylor’ and urges them to find her – but does Esther Taylor exist or is Mark Bretherick making it up to protect himself?

Sally studies the photographs at home and realises she knows where they were both taken – the same spot at the bird sanctuary. She leaves a voicemail on Esther’s phone saying she’s heading there to try and get to the bottom of it. Esther is just leaving work… and she’s being followed. We see her make her way to her car and turn, wide-eyed when she realises that a man’s footsteps are rapidly approaching…

Sally speaks to a woman who works at the Bird Sanctuary. The woman asks her to sign the visitor’s book, which she does but as ‘Esther Taylor’. Sally shows her the photographs but the woman doesn’t recognise the woman and child in the picture. She then sees the other photo of Geraldine and Lucy and recognises them from the news. The woman becomes immediately suspicious. Sally flees as the woman threatens to call the police and does so. Charlie and Simon arrive at the Bird Sanctuary looking for ‘Esther Taylor’. But they are too late. As Charlie emerges from the bird sanctuary office with the photographs that ‘Esther Taylor’ left behind, Sally is unconscious in the backseat of a dark car and being driven away, into the country.

Monday, 2 May 2011, 9:00PM – 10:00PM ITV1

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