‘He—it was most unfortunate. A little mistake. I assure you I did not see who it was. I mean as soon as he realized it was the wrong door he went out again. Naturally. The inner door being half-glass made it even more unfortunate though of course there being two rooms was—was better for all concerned than if it was the usual arrangement. And I mean that he didn’t see me so that in a way it didn’t matter. It didn’t really matter a scrap. Not a scrap.’

Alleyn, listening to this rigmarole, sent his memory back to the top gallery of Marsdon House. He remembered the Victorian ante-room that opened off the landing, the inner gloomy sanctum beyond. The chaotic fragments of Miss Harris’s remarks joggled together in his brain and then clicked into a definite pattern.

‘Not a scrap, really,’ Miss Harris still repeated.

‘Of course not,’ agreed Alleyn cheerfully. ‘I think I understand what happened. Tell me if I go wrong. While you were still in the inner room the man who had interrupted Lord Robert’s telephone conversation came out of the green sitting-room and blundered through the wrong door into the ante-room of the ladies’ lavatory. That it?’

Miss Harris blanched at the unfortunate word but nodded her head.

‘Why are you so sure it was this same man, Miss Harris?’

‘Well, because, because I heard their voices as they came to the door of the next room and then Lord Robert’s voice on the landing and then—then it happened. I just knew that was who it was.’

Alleyn leant forward.

‘The inner door,’ he said, ‘is half-glass. Could you see this intruder?’

‘Dimly, dimly,’ cried Miss Harris. ‘Greatly obscured, I assure you. I’m sorry to say I forgot for some seconds to switch off my light. The other was on.’

‘So you actually could see the shape of this person, however shadowy, through the clouded glass?’

‘Yes. For a second or two. Before he went away. I think perhaps he was feeling unwell.’

‘Drunk?’

‘No, no. Certainly not. It was not a bit like that. He looked more as if he’d had a shock.’

‘Why?’

‘He—the shape of him put its hands to its face and it swayed towards the glass partition and for a moment leant against it. Thank God,’ said Miss Harris with real fervour, ‘I had locked the door.’

‘The silhouette would be clearer, more sharply defined, as it came closer to the door?’

‘I suppose so. Yes, it was.’

‘Still you did not recognise it?’

‘No. Never for an instant.’

‘Suppose—for the sake of argument, I were to say this man was either Sir Herbert Carrados, Captain Withers, the waiter on the landing, Mr Donald Potter, or Dimitri the caterer. Which would you think most likely?’

‘I don’t know. Perhaps Dimitri. I don’t know.’

‘What height?’

‘Medium.’

‘Well,’ said Alleyn, ‘what happened next?’