‘You didn’t do anything, then?’ asked Miss Helier.

‘My dear young lady, what could I do? There was no evidence. The majority of the eye-witnesses told the same story as Miss Barton. I had built up my own suspicions out of a fleeting expression which I might possibly have imagined. The only thing I could and did do was to see that the widest inquiries were made for the relations of Amy Durrant. The next time I was in England I even went and saw the landlady of her room, with the results I have told you.’

‘But you felt there was something wrong,’ said Miss Marple.

Dr Lloyd nodded.

‘Half the time I was ashamed of myself for thinking so. Who was I to go suspecting this nice, pleasant-mannered English lady of a foul and cold-blooded crime? I did my best to be as cordial as possible to her during the short time she stayed on the island. I helped her with the Spanish authorities. I did everything I could do as an Englishman to help a compatriot in a foreign country; and yet I am convinced that she knew I suspected and disliked her.’

‘How long did she stay out there?’ asked Miss Marple.

‘I think it was about a fortnight. Miss Durrant was buried there, and it must have been about ten days later when she took a boat back to England. The shock had upset her so much that she felt she couldn’t spend the winter there as she had planned. That’s what she said.’

‘Did it seem to have upset her?’ asked Miss Marple.

The doctor hesitated.

‘Well, I don’t know that it affected her appearance at all,’ he said cautiously.

‘She didn’t, for instance, grow fatter?’ asked Miss Marple.

‘Do you know—it’s a curious thing your saying that. Now I come to think back, I believe you’re right. She—yes, she did seem, if anything, to be putting on weight.’

‘How horrible,’ said Jane Helier with a shudder. ‘It’s like—it’s like fattening on your victim’s blood.’

‘And yet, in another way, I may be doing her an injustice,’ went on Dr Lloyd. ‘She certainly said something before she left, which pointed in an entirely different direction. There may be, I think there are, consciences which work very slowly—which take some time to awaken to the enormity of the deed committed.

‘It was the evening before her departure from the Canaries. She had asked me to go and see her, and had thanked me very warmly for all I had done to help her. I, of course, made light of the matter, said I had only done what was natural under the circumstances, and so on. There was a pause after that, and then she suddenly asked me a question.

‘ “Do you think,” she asked, “that one is ever justified in taking the law into one’s own hands?”

‘I replied that that was rather a difficult question, but that on the whole, I thought not. The law was the law, and we had to abide by it.