‘They talked during the fight. Here.’ He flattened out his Penguin copy of the play. ‘I got this out of a dressing room,’ he said. ‘Look. The dialogue was cut pretty severely but there’s enough left. Macbeth gets the last word. “And damned,”’ quoted Mr Fox who read laboriously through his specs, ‘“be him that first cries, ‘Hold, enough!’” and with that they set to again. And within the next three minutes, whoever did it, his head was off his shoulders and on the stick.’

‘Our case in a nutshell, Br’er Fox.’

‘Yerse.’

‘And now, if you will, let me examine what may or may not be the side issues in evidence. Where’s Peregrine Jay? Has he gone with the others?’

‘No,’ said Peregrine, ‘I’ve been here all the time.’ And he came down the centre aisle into the light. ‘Here I am,’ he said. ‘Not as bright as a button, I fear, but here.’

‘Sit down. Did you hear what I said?’

‘Yes. I’m glad you said it. I’m going to break my own rule and tell you more fully of what may be, as you’ve hinted, side issues.’

‘I’ll be glad to hear you.’

Peregrine went on. He described the unsettling effect of the tales of ill-luck that had grown up round the play of Macbeth and his own stern injunctions to the company that they should ignore them.

‘The ones most committed, of course, like Nina Gaythorne, didn’t obey me but I think, though I can’t be sure, that on the whole they were more or less obeyed. For a time, at any rate. And then it began. With the Banquo mask in the King’s room.’

He described it. ‘It was extraordinarily effective. Glaring there in the shadow. It’s like all Gaston’s work, extremely macabre. You remember the procession of Banquos in the witches’ scene?’

‘I do indeed.’

‘Well, to come upon one suddenly! I was warned but even then – horrid!’

‘Yes.’

‘I examined it and I found the arrangement of string connected with the slate-coloured poncho. The head itself was fixed on a coat-hanger and the poncho hung from that. The long end of string reached down to the stage. There is a nail in the wall above the head. The string passed over it and down. To stage level. Now it seemed to me, it still seems to me, that if I’m on the right track this means that the cloak was pulled up to cover the head and the cord fastened down below. I’ve had a look and there’s a crosspiece in the back of the scenery in exactly the right place.’

‘It could be lowered from stage level?’

‘Yes. The intention being that it remained hidden until Macduff went in.’

‘Macduff saw it first. He tried to warn Macbeth.’

‘What did you do with it?’