Assessed correctly, each had its particular place in a particular universe. Assembled in their proper place in their particular universe, they not only made sense, they made a picture. In other words, Hercule Poirot was doing a jigsaw puzzle.

He looked down at where a rectangle still showed improbably shaped gaps. It was an occupation he found soothing and pleasant. It brought disorder into order. It had, he reflected, a certain resemblance to his own profession. There, too, one was faced with various improbably shaped and unlikely facts which, though seeming to bear no relationship to each other, yet did each have its properly balanced part in assembling the whole. His fingers deftly picked up an improbable piece of dark grey and fitted it into a blue sky. It was, he now perceived, part of an aeroplane.

‘Yes,’ murmured Poirot to himself, ‘that is what one must do. The unlikely piece here, the improbable piece there, the oh-so-rational piece that is not what it seems; all of these have their appointed place, and once they are fitted in, eh bien, there is an end of the business! All is clear. All is – as they say nowadays – in the picture.’

He fitted in, in rapid succession, a small piece of a minaret, another piece that looked as though it was part of a striped awning and was actually the backside of a cat, and a missing piece of sunset that had changed with Turneresque suddenness from orange to pink.

If one knew what to look for, it would be so easy, said Hercule Poirot to himself. But one does not know what to look for. And so one looks in the wrong places or for the wrong things. He sighed vexedly. His eyes strayed from the jigsaw puzzle in front of him to the chair on the other side of the fireplace. There, not half an hour ago, Inspector Bland had sat consuming tea and crumpets (square crumpets) and talking sadly. He had had to come to London on police business and that police business having been accomplished, he had come to call upon M. Poirot. He had wondered, he explained, whether M. Poirot had any ideas. He had then proceeded to explain his own ideas. On every point he outlined, Poirot had agreed with him. Inspector Bland, so Poirot thought, had made a very fair and unprejudiced survey of the case.

It was now a month, nearly five weeks, since the occurrences at Nasse House. It had been five weeks of stagnation and of negation. Lady Stubbs’ body had not been recovered. Lady Stubbs, if living, had not been traced. The odds, Inspector Bland pointed out, were strongly against her being alive. Poirot agreed with him.

‘Of course,’ said Bland, ‘the body might not have been washed up. There’s no telling with a body once it’s in the water. It may show up yet, though it will be pretty unrecognizable when it does.’