“The Marquis,” he said, “the Marquis? Do you think he is mixed up in this affair, M. Poirot?”

“I ask you what you know of him.”

The Commissary made an expressive grimace.

“Not as much as we should like to,” he observed ruefully. “He works behind the scenes, you understand. He has underlings who do his dirty work for him. But he is someone high up. That we are sure of. He does not come from the criminal classes.”

“A Frenchman?”

“Y‑es. At least we believe so. But we are not sure. He has worked in France, in England, in America. There was a series of robberies in Switzerland last autumn which were laid at his door. By all accounts he is a grand seigneur , speaking French and English with equal perfection, and his origin is a mystery.”