‘Maybe I can guess what you’re thinking, M. Poirot, but I assure you there was nothing of that kind. It wasn’t fitted up for smuggling if that’s what you mean. There were no fancy hidden partitions or secret cubby-holes. We’d have found them if there had been. There was nowhere on it you could have stowed away a body.’

‘You are wrong, mon cher, that is not what I mean. I only asked what kind of yacht, big or small?’

‘Oh, it was very fancy. Must have cost the earth. All very smart, newly painted, luxury fittings.’

‘Exactly,’ said Poirot. He sounded so pleased that Inspector Bland felt quite surprised.

‘What are you getting at, M. Poirot?’ he asked.

‘Etienne de Sousa,’ said Poirot, ‘is a rich man. That, my friend, is very significant.’

‘Why?’ demanded Inspector Bland.

‘It fits in with my latest idea,’ said Poirot.

‘You’ve got an idea, then?’

‘Yes. At last I have an idea. Up to now I have been very stupid.’

‘You mean we’ve all been very stupid.’

‘No,’ said Poirot, ‘I mean specially myself. I had the good fortune to have a perfectly clear trail presented to me, and I did not see it.’

‘But now you’re definitely on to something?’

‘I think so, yes.’

‘Look here, M. Poirot –’

But Poirot had rung off. After searching his pockets for available change, he put through a personal call to Mrs Oliver at her London number.

‘But do not,’ he hastened to add, when he made his demand, ‘disturb the lady to answer the telephone if she is at work.’

He remembered how bitterly Mrs Oliver had once reproached him for interrupting a train of creative thought and how the world in consequence had been deprived of an intriguing mystery centring round an old-fashioned long-sleeved woollen vest. The exchange, however, was unable to appreciate his scruples.

‘Well,’ it demanded, ‘do you want a personal call or don’t you?’

‘I do,’ said Poirot, sacrificing Mrs Oliver’s creative genius upon the altar of his own impatience. He was relieved when Mrs Oliver spoke. She interrupted his apologies.

‘It’s splendid that you’ve rung me up,’ she said. ‘I was just going out to give a talk on How I Write My Books. Now I can get my secretary to ring up and say I am unavoidably detained.’

‘But, Madame, you must not let me prevent –’