“And Mr. Van Aldin?” he queried doubtfully.

“ M. Van Aldin is an obstinate man,” said Poirot drily. “I do not argue with obstinate men. I act in spite of them. We will go and see the lady immediately. I will tell her that you are empowered by M. Van Aldin to act for him, and you will guard yourself well from contradicting me.”

Knighton still looked slightly doubtful, but Poirot took no notice of his hesitation.

At the hotel, they were told that Mademoiselle was in, and Poirot sent up both his and Knighton’s cards, with “From Mr. Van Aldin” pencilled upon them.