Jeremy sighed and began to speak again.

‘Then Lord Berrow asked leave to pay his addresses. We told her he would be calling in the morning and she was to accept. We had such hopes. Berrow had spoken to me. He said once he was married to Dolly and I had finished my studies at Oxford, he could get me a good living, maybe even in Mayfair. He also said he would speak to the archbishop and get my father somewhere better than Apton Magna. We were so full of hope. We were so happy.

‘Then Dolly began to scream that she would not do it, that she was going to run away. She went to her room.

‘My parents sent me to see her. She defied me. She dared to laugh in my face. Me! That cuckoo in our family nest, that bastard, dared to laugh at me. I was blind with rage. I went to my room and got a dagger, a Turkish one, that someone had given me.

‘I went back to her room and held it on her. “You will do as you’re told,” I said, “or I will kill you.”

‘She laughed again. “You! You’re not a man like my Roger,” she said. “You wouldn’t dare.”

‘That’s when I stabbed her. There was blood everywhere. My parents came rushing in.

‘We knew we had to get her away from the house. At the ball we’d seen her slipping a note to Lady Rose, and we stole it. We knew she planned to meet Lady Rose at the Serpentine. We thought, let Lady Rose find the body. With luck they’ll think she did it.

‘We’d had that Lady of Shalott costume made for her, because her engagement was to be announced at the fancy-dress party the following week. We cleaned her and dressed her in it. I got the carriage round from the mews, and we put her in it and took her down to the Serpentine and laid her out in that rowing-boat. My father said prayers over her. Somehow it eased the horror to see her lying there so calm and beautiful.

‘In the morning, we gathered all the servants together. We told them Dolly had run away. One asked what all the commotion the previous night had been about. I told them if they said anything about it they would lose their jobs.’

‘So why did you go after Lady Rose?’ asked Kerridge.

‘The newspapers implied she was holding something back. I was terrified. I went to see that villain, Bolton. When I visited him in prison, he told me he would do anything for money. I never thought at that time that I would have any use for him. But I needed him. The only gun we had was a lady’s purse gun. I gave that to him.

‘Then the temporary footman, Will, started blackmailing us. He had been awake during the night and had seen us carry a body into the carriage. I knew he would bleed us dry, so I called on him and finished him. That is all. You may release my parents.’