‘We all had tea at The Flat Hat in Vincent Square.’

‘And then?’

‘Ormerin suggested we should go to an exhibition of poster work at the Westminster. We did go, and met some people we knew.’

‘Their names, please, Miss Lee.’

She gave him the names of half a dozen people and the addresses of two.

‘When did you leave the Westminster Art School?’

‘I don’t know. About six, I should think. Ormerin had a date somewhere. Hatchett and I had dinner together at a Lyons. He took me. Then we went to the show at the Vortex Theatre.’

‘That’s in Maida Vale, isn’t it?’

‘Yes. I’m a subscriber and I had tickets. They were doing a play by

Michael Sasha. It’s called Angle of Incidence. It’s frightfully thrilling and absolutely new. All about three County Council labourers in a sewer. Of course,’ added Miss Lee, adopting a more mature manner, ‘the Vortex is purely experimental.’

‘So it would seem. Did you speak to anyone while you were there?’

‘Oh yes. We talked to Sasha himself, and to Lionel Shand who did the décor. I know both of them.’

‘Can you give me their addresses?’

Miss Lee was vague on this point, but said that care of the Vortex would always find them. Patiently led by Alleyn she gave a full account of her weekend. She had stayed with an aunt in the Fulham Road, and had spent most of her time in this aunt’s company. She had also seen a great deal of Watt Hatchett, it seemed, and had gone to a picture with him on Saturday night.

‘Only I do hope you won’t have to ask Auntie anything, Inspector Alleyn, because you see she pays my fees with Miss Troy, and if she thought the police were after me she’d very likely turn sour, and then I wouldn’t be able to go on painting. And that,’ added Miss Lee with every appearance of sincerity, ‘would be the most frightful tragedy.’

‘It shall be averted if possible,’ said Alleyn gravely, and got the name and address of the aunt.

‘Now then, Miss Lee, about those two conversations you overheard—’

‘I don’t want to be called as a witness,’ began Miss Lee in a hurry.

‘Possibly not. On the other hand you must realize that in a serious case—and this is a very serious case—personal objections of this sort cannot be allowed to stand in the way of police investigation.’

‘But I didn’t mean you to think that because Bostock flew into a blind rage with Sonia she was capable of murdering her.’

‘Nor do I think so. It appears that half the class flew into rages at different times, and for much the same reason.’

‘I didn’t! I never had a row with her. Ask the others. I got on all right with her. I was sorry for her.’

‘Why?’