‘Florence took charge of it. I’m afraid,’ Fox said, ‘I’m not with you, Mr Alleyn, in respect of the scent.’

‘My dear old boy, think! Think of the bottle.’

‘Very big,’ Fox said judiciously.

‘Exactly. Very big. Well, then – ?’

‘Yes. Ah, yes,’ Fox said, and then: ‘Well, I’ll be staggered!’

‘And so you jolly well should. This could blow the whole damn’ case wide open again.’

‘Will I fetch them?’

‘Do. And call on Florence, wherever she is. Get the whole story, Fox. Tactfully, as usual. Find out when the scent was decanted into the spray and when she used it. Watch the reactions, won’t you? And see if there’s anything in the Plumtree stories: about Richard Dakers’s parentage and Florence being threatened with the sack.’

Fox looked at his watch. ‘Ten o’clock,’ he said. ‘She may have gone to bed.’

‘That’ll be a treat for you. Leave me your notes. Away you go.’

While Fox was on this errand, Alleyn made a plot, according to information, of the whereabouts of Charles Templeton, the four guests, the servants and Richard Dakers up to the time when he himself arrived on the scene. Fox’s spadework had been exhaustive, as usual, and a pretty complicated pattern emerged. Alleyn lifted an eyebrow over the result. How many of them had told the whole truth? Which of them had told a cardinal lie? He put a query against one name and was shaking his head over it when Fox returned.

‘Bailey’s finished with them,’ Fox said, and placed on Richard’s desk the scent spray, the empty ‘Unguarded’ bottle and the tin of Slaypest.

‘What’d he find in the way of dabs?’

‘Plenty. All sorts, but none that you wouldn’t expect. He’s identified the deceased’s. Florence says she and Mr Templeton and Colonel Warrender all handled the exhibits during the day. She says the deceased got the colonel to operate the spray on her, just before the party. Florence had filled it from the bottle.’

‘And how much was left in the bottle?’

‘She thinks it was about a quarter full. She was in bed,’ Fox added in a melancholy tone.

‘That would tally,’ Alleyn muttered. ‘No sign of the bottle being knocked over and spilling, is there?’

‘None.’

Alleyn began to tap the Slaypest tin with his pencil.

‘About half-full. Anyone know when it was first used?’

‘Florence reckons a week ago. Mr Templeton didn’t like her using it and tried to get Florence to make away with it.’

‘Why didn’t she?’

‘No chance according to her. She went into a great taking-on and asked me if I was accusing her of murder.’

‘Did she get the sack, this morning?’

‘When I asked her she went up like a rocket bomb, the story being that Mrs Plumtree has taken against her and let out something that was told in confidence.’