“Like the beginning of a novel, eh? Real exciting stuff. Wouldn’t believe it if you read about it.”

Poirot did not speak. He was very thoughtful. All the evening he had hardly opened his lips.

“What says the master detective, eh?” asked Hawker, clapping him on the back. “Nothing to work your grey cells over this time.”

“You think not?”

“What could there be?”

“Well, for example, there is the window.”

“The window? But it was fastened. Nobody could have got out or in that way. I noticed it specially.”

“And why were you able to notice it?”

The doctor looked puzzled. Poirot hastened to explain.