‘I hope,’ Alleyn said. ‘You will all feel perfectly free to interrupt at any point. About this possibility of drugging. If the brandy was drugged, then of course we shall find out. Moreover it must have been tinkered with after he went on for his final scene. Indeed, any use of a drug, and one cannot disregard the possibility of even the most fantastic methods, must surely have been prepared while he was on the stage during the last act. We shall, of course, have a chemical analysis made of everything he used—the brandy, his tumbler, his cigarettes, his make-up and even the greasepaint on his face. I tell you, quite frankly, that I’ve no idea at all whether this will get us any further.’

Fox cleared his throat. This modest sound drew the attention of the company upon him but he merely looked gravely preoccupied and they turned back to Alleyn.

‘Following out this line of thought it seems clear,’ he said, ‘that two visits would have to be made to the dressing-room. The first, during his scene in the last act and the second, after he had come off and before the smell of gas was first noticed: by Mr Parry Percival.’

Percival said in a high voice: ‘I knew this was coming.’ Gay Gainsford turned and looked at him with an expression of the liveliest horror. He caught her eye and said: ‘Oh, don’t be fantastic, Gay darling. Honestly!’

‘Mr Percival,’ Alleyn said, ‘whose room is next to Mr Bennington’s and whose fire backs on his, noticed a smell of gas when he was about to go out for the curtain-call. He tells us he is particularly sensitive to the smell because of its association in this theatre and that he turned his own fire off and went out. Thus his fingerprints were found on the tap.’

‘Well, naturally they were,’ Parry said angrily. ‘Really, Gay!’

‘This, of course,’ Alleyn went on, ‘was reminiscent of the Jupiter case but in that case the tube was not disconnected because the murderer never entered the room. He blew down the next-door tube and the fire went out. In that instance the victim was comatose from alcohol. Now, it seems quite clear to us that while this thing was planned with one eye on the Jupiter case, there was no intention to throw the blame upon anyone else and that Mr Percival’s reaction to the smell was not foreseen by the planner. What the planner hoped to emphasize was Mr Bennington’s absorption in the former case. We were to suppose that when he decided to take his own life he used the method by which he was obsessed. On the other hand,’ Alleyn said, ‘suppose this hypothetical planner was none other than Bennington himself?’