James stood over her as he phoned Control and summoned backup. Then he sat beside her and asked her if there was anything he could get her.

She shook her head tearily.

‘I need to know if you meant what you told us, Mrs Prescott,’ he said. ‘Or did you say it because you know that your son killed Rachel and you want to take the blame for him?’

She shook her head. ‘No, it was me. Not Ethan. And I didn’t tell him what I did. I just hoped he would never find out.’

‘We’ll carry out a formal interview at the station, but can you please explain to me what happened?’

She turned to face him, her lower lip trembling. ‘I was with Ethan on the terrace when Libby approached us and told Ethan she wanted to talk to him. She told him she would go and wait behind the bushes next to the path and he went and met her. When he came back, about twenty minutes later, he told me what had happened with Rachel. I was shocked and urged him to go and find her to stop her making mischief. But he didn’t think she was serious so he wouldn’t. So, I took it upon myself to sort it as I didn’t want her to ruin everything. I told him I needed to use the loo, but instead of going inside I slipped into the garden and followed the path all the way to the lake. And that’s where she was. It was freezing cold, but she didn’t seem to care. She was standing on the jetty and staring out over the water, as still as a statue.’

‘What did you do?’

‘I walked up to her. She turned and even though it was quite dark I could see she’d been crying. She didn’t seem surprised to see me and so I started trying to talk sense into her. I urged her not to betray her sister, but she was having none of it. She said she was fed up with bad things happening to her and not to Libby. And she accused me of being sick and twisted for coming up with the plan to get some of the Murphy money.’

She paused then, as though the words were stuck in her throat.

‘Is that when it turned ugly?’ James asked.

It took her a few more seconds to find her voice. When she did, she said, ‘She flipped suddenly. Told me I’d never loved her and that Libby had always been my favourite, which hurt because it wasn’t true. I reached out to take her hand but she responded by pushing me away. I almost lost my balance and it was only thanks to my walking stick that I didn’t fall into the lake.

‘Rachel then said she hated me and that she wished I was dead. I lost it then and lashed out with the stick. It caught her on the chest and she called me a bitch and tried to punch me. So, I hit her again and as she stumbled backwards, I kept on doing it. She managed to fend off most of the blows with her arms but then I struck her face again and her glasses fell off and she dropped her purse. I should have stopped then but I saw red and I just couldn’t. The next blow was hard enough to knock her over and her head landed on one of the jetty posts. I saw she was hurt, but it took a while for me to realise that she was dead. And that was when I panicked. I looked around and there was no one in sight so I did the only thing I could think of doing and pushed her into the lake.’