The aftermath of Gary Webster’s suicide begins – a DPS enquiry, a very shaken Palmer, and a shocked but stoic Gemma, still convinced of a cover up at the hospital. Gary wasn’t the killer; all he ever wanted was a straight answer.

Adrian Lawson offers a video recording of Amber’s surgery, showing that it was purely straightforward procedure, nothing untoward. His helpful nature doesn’t convince Connor, noting that he wouldn’t have given them something that might implicate either him or the hospital. In any case, Amber died in the ICU, six hours after the surgery. To get to the truth, they need to go back to whoever was in the ICU that night.

Walker is reticent about what he sees as his team wasting their time investigating hospital negligence, when Carlisle’s killer has still not been found. However, Connor is convinced of a connection between his murder and the death of the Webster’s little girl. Connor’s hunch nags at Walker and he pays a discreet visit to Gemma Webster. Promising that the police are investigating the case fully and properly, and revealing that Carlisle was killed with a massive overdose of fentanyl, he asks her once more if she has any information she hasn’t revealed so far. Gemma says nothing.

Carlisle and Neelah both gave statements to the hospital enquiry panel about the Amber Webster case, the day before Carlisle was murdered. Walker unearths them, Connor reads them. They state that Carlisle gave clear instructions which Adrian Lawson failed to follow. In other words, the culpability for Amber’s death is being laid squarely with Lawson. Back at the hospital, Palmer questions Nurse Claire Jenkin, who was on duty in the ICU the night that Amber died. She contradicts the statements, Lawson took the instruction for Amber’s care over the phone from Carlisle and implemented it fully and properly.

With the spotlight of suspicion now falling on Lawson, Walker questions the Lawsons again. Adrian expresses shock and surprise when told that he was being implicated in Amber’s death. He refutes them, that he had followed Carlisle’s instructions to the letter. Adrian’s loyalty to his former boss and mentor starts to fade as, seething, he suggests that Walker look at what Carlisle was up to that night.

Gemma Webster visits Connor at the police station. She tells Connor that Gary suffered from crippling arthritis and shows Connor one of his prescriptions – for fentanyl. Gemma tells Connor that she needs to know for certain if her husband is a murderer. Despite the fentanyl revelation, it has been confirmed by the mortuary attendant that Gary was there all evening, well into the early hours – Webster is definitely in the clear.

Palmer’s dogged detective work reveals that Neelah has been lying to them. She had claimed she was with Carlisle the night Amber died. In fact she was at a conference in Liverpool, though Nurse Claire tells Palmer that a woman did answer the phone that night, and not a voice she recognised. Meanwhile, Satch has been going through the stash of photographs from Gary Webster’s flat, and he finds one showing Carlisle and Sally Lawson, where it shows they are certainly more than just friends.

Walker ambushes the Lawson’s at their house, asking for an explanation for the suggestive photograph. They give a fine performance of solidarity, Sally claiming that Jonathan was just an outrageous flirt. Knowing that Walker hasn’t bought their performance, the next day Sally goes to talk to Walker, admitting that she and Carlisle were having an affair but Adrian didn’t know, and in no way were either of them involved in Carlisle’s murder.

When CCTV reveals that Carlisle snatched Webster’s camera, SOCOs hunt it out and find it at his house. On it are photos that Webster hadn’t downloaded, from the night of the murder – Sally and Carlisle kissing and laughing as they go inside his house that evening. Both Sally and Adrian Lawson are brought in for formal questioning. Under careful and deliberate interrogation, slowly their story starts to break down. Adrian is goaded and provoked by Connor and Walker, his wife screwing his boss right under his nose, and his boss about to screw up his career by blaming him for Amber’s death. With Sally, it’s the threat of a long prison sentence, away from her children, that finally makes her crack.

The full truth of what happened that evening finally comes out – Adrian arrived to catch Sally in Carlisle’s bed. Carlisle just laughed, nonchalant about what he had done. A seething Adrian struck Carlisle with a heavy paperweight, knocking him out. Then he thought he could try to make it look like an overdose, by injecting the massive dose of fentanyl, bullying Sally into helping by cleaning up. The needle and the ampoules left out to make the overdose look convincing had then been flushed away by Neelah Sahjani, thinking she was walking in on a suicide. Adrian Lawson is charged with the murder of Jonathan Carlisle.

Thursday 7 February 2008 9:00pm – 10:00pm on ITV1.