‘And now,’ said Hemingway, ‘you’ll find that the gardener’s had the key on him ever since midday yesterday. A fine sort of case this is!’

The Sergeant said, hiding a grin: ‘I thought you liked them difficult, sir.’

‘So I do,’ retorted Hemingway. ‘But I like something you can catch hold of! Here, every time I think I’ve got a line on something, it slips out of my grasp like something in a bad dream. If there’s a sliding panel in that room, I’ll eat my hat; I’d go to the stake no one tampered with that door-key; and now it begins to look as though the window wasn’t touched either. It’s witchcraft, that’s what it is, or else I’m getting past my job.’

‘It is a fair stinker,’ agreed the Sergeant. ‘No use thinking about the chimney, I suppose?’ The Inspector cast him a look of dislike.

‘Or the roof,’ suggested the Sergeant. ‘There are attics above the bedrooms, and there are dormer-windows. Could a chap have got through the one over Mr Herriard’s room, and reached the window below?’

‘No, he couldn’t,’ said Hemingway crossly. ‘I’ve already looked into that, which just shows you the sort of state I’m getting into, for a more fatheaded idea I’ve never met. You’ll have to go off and interview this gardener, but you can drop me at the station first.’

‘All right, sir. But I can’t help feeling that I shall find he’s had the key all the time.’

‘If you didn’t, I should very likely drop down in a fit,’ responded Hemingway.

They drove back to the police-station in depressed silence. Hemingway alighted there and went into the building. He found Inspector Colwall fortifying himself with very strong tea, and thankfully accepted a cup of this beverage.

‘How are you getting on?’ asked Colwall.

‘I’m not,’ replied Hemingway frankly. ‘It reminds me of the Hampton Court maze more than of anything else. It doesn’t matter what path you take: you always find yourself back at the starting-point again. Seems to me I’m trying to catch up with a regular Houdini. Handcuffs and locked chests would be nothing to this bird.’

‘I don’t mind telling you I was glad to hand over the case to you,’ confided Colwall. ‘Of course, detection isn’t, properly speaking, my line.’

‘It won’t be mine by the time I’m through with this,’ said Hemingway, sipping his tea. ‘Here I’ve got no fewer than four hot suspects, and three possibles, all without alibis, and most of them with life-size motives, and I’m damned if I see my way to bringing it home to any of them.’

‘Four hot suspects?’ said Colwall, working it out in his mind.

‘Young Stephen, his sister, Mottisfont, and Roydon,’ said Hemingway.

‘You don’t reckon the fair young lady could have done it?’

‘I’ve put her in as a possible, but I wouldn’t lay a penny on her myself.’

‘Who are your other possibles, if you don’t mind my asking?’

‘The valet and the butler.’