“Instinct is a marvellous thing,” mused Poirot. “It can neither be explained nor ignored.”

“You and Miss Howard seem to know what you are talking about,” I observed coldly. “Perhaps you don’t realize that I am still in the dark.”

“Really? Is that so, mon ami?

“Yes. Enlighten me, will you?”

Poirot studied me attentively for a moment or two. Then, to my intense surprise, he shook his head decidedly.

“No, my friend.”

“Oh, look here, why not?”

“Two is enough for a secret.”

“Well, I think it is very unfair to keep back facts from me.”

“I am not keeping back facts. Every fact that I know is in your possession. You can draw your own deductions from them. This time it is a question of ideas.”