Whether it was the possibility of being subjected to this treatment or the sip of water that Darcey persuaded her to take or the generous thumps on her back, administered by Jacko, that effected a cure, the paroxysm abated. Alleyn, who had watched this scene thoughtfully, said: ‘If you are quite yourself again, Miss Gainsford, will you try to remember when you left the greenroom?’

She shook her head weakly and said in an invalid’s voice: ‘Please, I honestly don’t remember. Is it very important?’

‘Oh, for pity’s sake, Gay!’ cried Helena with every sign of the liveliest irritation. ‘Do stop being such an unmitigated ass. You’re not choking: if you were your eyes would water and you’d probably dribble. Of course it’s important. You were in the greenroom and next door to Ben. Think!’

‘But you can’t imagine—’ Gay said wildly. ‘Oh, Aunty—I’m sorry, I mean, Ella—I do think that’s a frightful thing to suggest.’

‘My dear Gay,’ Poole said, ‘I don’t suppose Ella or Mr Alleyn or any of us imagines you went into Ben’s room, knocked him senseless with a straight left to the jaw and then turned the gas on. We merely want to know what you did do.’

J.G. who had given a sharp ejaculation and, half-risen from his chair, now sank back.

Alleyn said: ‘It would also be interesting, Mr Poole, to hear how you knew about the straight left to the jaw.’

Poole was behind Martyn and a little removed from her. She felt his stillness in her own bones. When he spoke it was a shock rather than a relief to hear how easy and relaxed his voice sounded.

‘Do you realize, Alleyn,’ he said, ‘you’ve given me an opportunity to use, in reverse, a really smashing detective’s cliché. I didn’t know. You have just told me!’

‘And that,’ Alleyn said with some relish, ‘as I believe you would say in the profession, takes me off with a hollow laugh and a faint hiss. So you merely guessed at the straight left?’

‘If Ben was killed, and I don’t believe he was, it seemed to me to be the only way this murder could be brought about.’

‘Surely not,’ Alleyn said without emphasis. ‘There is the method that was used before in this theatre with complete success.’

‘I don’t know that I would describe as completely successful, a method that ended with the arrest of its employer.’

‘Oh,’ Alleyn said lightly, ‘that’s another story. He underestimated our methods.’

‘A good enough warning to anyone else not to follow his plan of action.’

‘Or perhaps merely a hint that it could be improved upon,’ Alleyn said. ‘What do you think, Mr Darcey?’

‘I?’ J.G. sounded bewildered. ‘I don’t know. I’m afraid I haven’t followed the argument.’

‘You were still thinking about the straight-left theory perhaps?’