‘What man?’ demanded the inspector, his mind switching from the unexpected introduction of the second gardener into the drama, to the further introduction of an unspecified man.

‘Freckles and a Yorkshire accent,’ said Mrs Oliver. ‘But, as I say, I’m not drunk and I’m not mad. I’m just upset. Thoroughly upset,’ she repeated, once more resorting to capital letters.

‘I’m sure, madam, it must have been most distressing,’ said the inspector.

‘The awful thing is,’ said Mrs Oliver, ‘that she wanted to be a sex maniac’s victim, and now I suppose she was – is – which should I mean?’

‘There’s no question of a sex maniac,’ said the inspector.

‘Isn’t there?’ said Mrs Oliver. ‘Well, thank God for that. Or, at least, I don’t know. Perhaps she would rather have had it that way. But if he wasn’t a sex maniac, why did anybody murder her, Inspector?’

‘I was hoping,’ said the inspector, ‘that you could help me there.’

Undoubtedly, he thought, Mrs Oliver had put her finger on the crucial point. Why should anyone murder Marlene?

‘I can’t help you,’ said Mrs Oliver. ‘I can’t imagine who could have done it. At least, of course, I can imagine – I can imagine anything! That’s the trouble with me. I can imagine things now – this minute. I could even make them sound all right, but of course none of them would be true. I mean, she could have been murdered by someone who just likes murdering girls but that’s too easy – and, anyway, too much of a coincidence that somebody should be at this fête who wanted to murder a girl. And how would he know that Marlene was in the boathouse? Or she might have known some secret about somebody’s love affairs, or she may have seen someone bury a body at night, or she may have recognized somebody who was concealing his identity – or she may have known a secret about where some treasure was buried during the war. Or the man in the launch may have thrown somebody into the river and she saw it from the window of the boathouse – or she may even have got hold of some very important message in secret code and not known what it was herself.’

‘Please!’ The inspector held up his hand. His head was whirling.

Mrs Oliver stopped obediently. It was clear that she could have gone on in this vein for some time, although it seemed to the inspector that she had already envisaged every possibility, likely or otherwise. Out of the richness of the material presented to him, he seized upon one phrase.

‘What did you mean, Mrs Oliver, by the “man in the launch”? Are you just imagining a man in a launch?’

‘Somebody told me he’d come in a launch,’ said Mrs Oliver. ‘I can’t remember who. The one we were talking about at breakfast, I mean,’ she added.