"Had he?"

Poirot shrugged his shoulders.

"That we shall never know."

"Doctor Roberts!" repeated Mrs. Oliver firmly. "Such a hearty man. Murderers are often hearty – as a disguise! If I were you, Superintendent Battle, I should arrest him at once."

"I daresay we would if there was a woman at the head of Scotland Yard," said Superintendent Battle, a momentary twinkle showing in his unemotional eyes, "But you see, mere men being in charge, we've got to be careful. We've got to get there slowly."

"Oh, men – men," sighed Mrs. Oliver and began to compose newspaper articles in her head.

"Better have them in now," said Superintendent Battle. "It won't do to keep them hanging about too long."

Colonel Race half rose. "If you'd like us to go -"

Superintendent Battle hesitated a minute as he caught Mrs. Oliver's eloquent eye. He was well aware of Colonel Race's official position and Poirot had worked with the police on many occasions. For Mrs. Oliver to remain was decidedly stretching a point. But Battle was a kindly man. He remembered that Mrs. Oliver had lost three pounds and seven shillings at bridge and that she had been a cheerful loser.

"You can all stay," he said, "as far as I'm concerned. But no interruptions, please (he looked at Mrs. Oliver) and there mustn't be a hint of what Monsieur Poirot has just told us. That was Shaitana's little secret and to all intents and purposes it died with him. Understand?"

"Perfectly," said Mrs. Oliver.

Battle strode to the door and called the constable who was on duty in the hall.

"Go to the little smoking-room. You'll find Anderson there with the four guests. Ask Doctor Roberts if he'll be so good as to step this way,"