"Is it really necessary to tell you, M. Poirot?" he asked.
"You are shrewd, M. Papopolous. No, it is not. They are not, for instance, worth five hundred thousand dollars."
Papopolous laughed, and Poirot joined with him.
"As an imitation," said Papopolous, handing them back to Poirot, "they are, as I said, quite excellent. Would it be indiscreet to ask, M. Poirot, where you came across them?"
"Not at all," said Poirot; "I have no objection to telling an old friend like yourself. They were in the possession of the Comte de la Roche."
M. Papopolous’ eyebrows lifted themselves eloquently.
"In-deed," he murmured.
Poirot leant forward and assumed his most innocent and beguiling air.
"M. Papopolous," he said, "I am going to lay my cards upon the table. The original of these jewels was stolen from Madame Kettering on the Blue Train. Now I will say to you first this: I am not concerned with the recovery of these jewels. That is the affair of the police. I am working not for the police but for M. Van Aldin. I want to lay hands on the man who killed Madame Kettering. I am interested in the jewels only in so far as they may lead me to the man. You understand?"
The last two words were uttered with great significance. M. Papopolous, his face quite unmoved, said quietly:
"Go on."