James and Abbott looked at each other across the bed. Abbott then took out her mobile phone and switched on the recorder. In response, Nash clenched his jaw

‘That’s for your benefit as well as ours,’ James explained to him. ‘And if at any point you feel you can’t continue then just say the word and we’ll stop.’

Nash grimaced as though in pain and took a long, deep breath.

‘Where shall I start?’ he asked, a crack in his voice.

‘First I’d like to know if it was you who installed the peephole in the wall,’ James said. ‘And tell us how you managed to do it.’

Nash twisted his mouth as he searched for words and when he spoke his voice was thick with emotion.

‘It goes back to when I did the work for Robert in the cellar,’ he said. ‘It was the first time I’d been down there without Charlotte. I knew that the door at the top of the steps led nowhere, but I was curious to see what was beyond it. I’d been given a set of keys and one of them unlocked it. That’s when I saw the concealed space between the door and the wall. As soon as I stepped inside, I heard Mary and Charlotte talking to each other in the living room. Their voices were as clear as day and I realised it was a way for me to find out what Charlotte really thought about me.’

He paused to gulp in some air before continuing.

‘The space wasn’t being used for anything and so I decided to make the most of it. I got my own key cut for the external door and stole the key to the internal door. Then for weeks afterwards I went there, usually late in the evening, and listened to their conversations. But it got to the stage where it wasn’t enough and I wanted to see them too. So, I bought a peephole online. I knew that the paper they had on the inside of the wall had been there for years and so I went looking for something that I thought would camouflage the hole. I came up with the raindrop design. I offered it to Robert for free. He liked it and he paid me to put it up. At the same time, I inserted the peephole.’

‘And how often did you go there to spy on them?’ James asked.

‘A couple of times a week. I wouldn’t have had to if Charlotte had moved in with me. But she wasn’t prepared to and so I was paranoid and insecure.’

‘And did you stay in there for hours at a time?’

‘I had nothing better to do and it always cheered me up when she said nice things about me to her parents.’

‘But how did you get away with it for so long?’ Abbott asked him.