"The doctor?"

"No, young Templeton. His trick with his bread. Do you remember what Flossie Monro told us before she died? That Claud Darrell had a habit of dabbing his bread on the table to pick up crumbs. Hastings, this is a vast plot, and that vacant-looking young man is our arch enemy—Number Four! Hurry."

I did not wait to argue. Incredible as the whole thing seemed, it was wiser not to delay. We scrambled down the ivy as quietly as we could and made a bee-line for the small town and the railway station. We were just able to catch the last train, the 8.34 which would land us in town about eleven o'clock.

"A plot," said Poirot thoughtfully. "How many of them were in it, I wonder? I suspect that the whole Templeton family are just so many agents of the Big Four. Did they simply want to decoy us down there? Or was it more subtle than that. Did they intend to play the comedy down there and keep me interested until they had had time to do—what? I wonder now."

He remained very thoughtful.

Arrived at our lodgings, he restrained me at the door of the sitting-room.

"Attention, Hastings. I have my suspicions. Let me enter first."

He did so, and, to my slight amusement, took the precaution to press on the electric switch with an old galosh. Then he went round the room like a strange cat, cautiously, delicately, on the alert for danger. I watched him for some time, remaining obediently where I had been put by the wall.

"It's all right, Poirot," I said impatiently.

"It seems so, mon ami, it seems so. But let us make sure."