It was at this juncture that Fox joined them, his excessively bland demeanour indicating, to Alleyn at least, that he had achieved his object and secured Pixie’s leash. The interview continued. Fox, as usual, managed to settle himself behind the subject and to take notes quite openly and yet entirely unnoticed. He had a talent for this sort of thing.

Mr Period’s conversation continued to be jumpy and disjointed, but gradually a fairly comprehensive picture of his ménage emerged. Alleyn heard of Cartell’s sister who was, of course, deeply shocked. ‘One of those red women who don’t normally seem to feel anything except the heat,’ Mr Period said oddly. ‘Never wear gloves and look, don’t you know, as if they never sit on anything but their hats or a shooting-stick. But I assure you she’s dreadfully cut up, poor Connie.’

Alleyn felt that Mr Period had invented this definition of Miss Cartell long ago and was so much in the habit of letting fly with it that it had escaped him involuntarily.

‘I mustn’t be naughty,’ he said unhappily. ‘Poor Connie!’ and looked exquisitely uncomfortable.

‘Apart from Miss Cartell and Lady Bantling, who I suppose is in one sense a connection or an ex-connection, are there any near relations?’

‘None that one would call near. It’s an old family,’ Mr Period said with a pale glance at his ruling passion, ‘but going – going. Indeed, I fancy he and Connie are the last. Sad.’

Alleyn said: ‘I’m afraid I shall have to ask you for an account of yesterday’s activities. I really am very sorry to pester you like this when you’ve had such a shock, but there it is. “Duty, duty must be done.”’

Mr Period brightened momentarily at this Gilbertian reference and even dismally hummed the tune, but the next second he was in the doldrums again. He worked backwards through the events of the previous day, starting with his own arrival in the lane, driven by Lady Bantling, at twenty past eleven. The plank bridge over the drain had supported him perfectly: the lamp was alight. As he approached the house he saw Mr Cartell at his bedroom window, which was wide open. Mr Cartell never, Mr Period explained, went to bed before one o’clock when he took Pixie out, but he often pottered about his room for hours before he retired. Alleyn thought he detected a note of petulance and also of extreme reticence.

‘I think,’ Mr Period said restlessly, ‘that Hal must have heard me coming home. He was at his window. He seemed – ah – he seemed to be perfectly well.’

‘Did you speak to him?’

‘I – ah – I – ah – I did just call out something after I came upstairs. He replied. I don’t remember – However!’

Mr Period himself, it transpired, had gone to bed, but not to sleep as the arrival and departure of treasure-hunters in the lane was disturbing. However, the last couple had gone before midnight and he had dozed off.