“But you believe that he meant to steal the rubies?”

“Certainly. There is no doubt as to that. See, I will recount to you the affair as I see it. The Comte knew of the rubies and he laid his plans accordingly. He made up a romantic story of a book he was writing, so as to induce your daughter to bring them with her. He provided himself with an exact duplicate. It is clear, is it not, that substitution is what he was after. Madame, your daughter, was not an expert on jewels. It would probably be a long time before she discovered what had occurred. When she did so⁠—well⁠—I do not think she would prosecute the Comte. Too much would come out. He would have in his possession various letters of hers. Oh yes, a very safe scheme from the Comte’s point of view⁠—one that he has probably carried out before.”

“It seems clear enough, yes,” said Van Aldin musingly.

“It accords with the personality of the Comte de la Roche,” said Poirot.