‘Water-mark, “Crescent Script”. People write these things,’ said Fox. ‘You know yourself there may be nothing in it. But we’ve got to take the usual notice. Talk to the super at the local station, I suppose. And the doctor who attended the old gentleman. He may be able to put the matter beyond doubt. There’s an end of it.’

‘He will if he can,’ said Alleyn grimly. ‘You may depend upon that.’

‘In the meantime, the AC suggested I should report to you and see about a chat with Mrs Alleyn. He remembered Mrs Alleyn had been at Ancreton before you came back.’

‘Report to me? If anything comes of this, does he want me to take over?’

‘Well, sir, I fancy he will. He mentioned, jokingly-like, that it’d be quite unusual if the investigating officer got his first statement on a case from his wife.’

‘Facetious ass!’ said Alleyn with improper emphasis.

Fox looked demurely down his nose.

‘Oh, well,’ said Alleyn, ‘let’s find Troy and we’ll hag over the whole blasted set up. She’s in the studio. Come on.’

Troy received Fox cheerfully. ‘I know what it’s all about, Mr Fox,’ she said, shaking hands with him.

‘I’m sure I’m very sorry—’ Fox began.

‘But you needn’t be,’ Troy said quickly, linking her arm through Alleyn’s. ‘Why on earth should you be? If I’m wanted, here I am. What happens?’

‘We sit down,’ Alleyn said, ‘and I go over the whole story as you’ve told it to me. When I go wrong, you stop me, and when you think of anything extra, you put it in. That’s all, so far. The whole thing may be a complete washout, darling. Anonymous letter writers have the same affection for the Yard that elderly naturalists have for The Times. Now then. Here, Fox, to the best of my ability, is the Ancred saga.’

He went methodically through Troy’s account, correlating the events, tracing the several threads in and out of the texture of the narrative and gathering them together at the end.

‘How’s that?’ he asked her when he had finished. He was surprised to find her staring at him as if he had brought off a feat of sleight of hand.

‘Amazingly complete and tidy,’ she said.

‘Well, Fox? What’s it amount to?’

Fox wiped his hand over his jaw. ‘I’ve been asking myself, sir,’ he said, ‘whether you mightn’t find quite a lot of circumstances behind quite a lot of sudden demises that might sound funny if you strung them together. What I mean to say, a lot of big houses keep rat-bane on the premises, and a lot of people can’t lay their hands on it when they want it. Things get mislaid.’

‘Very true, Foxkin.’