‘She’s taken poison,’ said Harry. He turned to the servants. ‘Send for a doctor. Miss Levine, take Lady Rose into another room, for God’s sake. Lady Rose, there is blood on your dress. Are you wounded?’

‘One of the steels in my stays came loose,’ said Rose with a hysterical laugh. ‘You knew she was going to poison herself, didn’t you?’

‘You are upset and don’t know what you are saying. We will talk later.’

By the time Kerridge lumbered up the stairs, Angela Stockton was dead. He had taken half an hour to arrive, and in that half-hour Harry, Becket, Rose and Daisy had a hurried consultation to get their stories right.

‘I want to know what you have all been up to,’ said Kerridge. The four had retreated to a morning-room on the same floor.

‘Lady Rose is still shocked,’ began Harry. ‘Mrs Stockton held a gun on her and was going to shoot her. Miss Levine managed to escape and came to look for me. Fortunately we saw her on the street and came here immediately.’

Kerridge turned his grey gaze on Rose. ‘Why was Mrs Stockton trying to kill you?’

‘I had been thinking and thinking about the murders,’ said Rose in a low voice. ‘I thought she might have committed them. I always thought she was mad. I came with Miss Levine and challenged her. She pulled out a gun and said she was going to shoot me. She confessed to both murders. She said she shot Mr Pomfret because he was blackmailing her. He had a photograph of her eating roast beef.’

Kerridge’s bushy eyebrows nearly vanished into his hairline. ‘Do you mean she killed twice over a plate of roast beef?’

‘She said she had built up a world-wide reputation as a vegetarian. She said Mrs Jerry was going to the police. She said Mr Pomfret had a picture of her in a compromising position with a young footman. Although she did not have the evidence, Mrs Jerry thought she had.’

‘And what was Lord Alfred being blackmailed about?’

‘I believe it was because he had got a servant girl pregnant and she died in childbirth,’ said Harry smoothly. ‘We only have what Mrs Stockton told Lady Rose. There is no proof of that.’

‘The press are going to have a field day with this,’ said Kerridge.

‘I think it would be better,’ said Harry, ‘if we stick to the roast beef blackmail. We cannot mention the other two because there is no evidence.’

‘At least Mrs Stockton saved us a court case. Did you not guess she was going to poison herself?’

‘How could I?’ said Harry. ‘She said it was heart medicine.’

‘I don’t believe you. There’s a lot in your statements I don’t believe. But I’m very glad to have two murders solved.’

‘May we please leave further questioning until tomorrow?’ asked Harry. ‘Lady Rose has been through the most terrible ordeal.’