The whistle blew, and we all trooped up into the Pullman car. Then, with a slow, unwilling jerk, the train drew out of the station.

It was a curious journey. The Scotland Yard men crowded together. Maps of Northern France were spread out, and eager forefingers traced the lines of roads and villages. Each man had his own pet theory. Poirot showed none of his usual loquacity, but sat staring in front of him, with an expression on his face that reminded me of a puzzled child. I talked to Norman, whom I found quite an amusing fellow. On arriving at Dover Poirot’s behaviour moved me to intense amusement. The little man, as he went on board the boat, clutched desperately at my arm. The wind was blowing lustily.

“ Mon Dieu! ” he murmured. “This is terrible!”

“Have courage, Poirot,” I cried. “You will succeed. You will find him. I am sure of it.”