Both the other men looked at him in some surprise.

"You must not be shocked or alarmed at what I am about to say. Supposing, Monsieur Van Aldin, that, after all, Monsieur Derek Kettering did not murder his wife?"

"What?"

Both men stared at him in blank surprise.

"Supposing, I say, that Monsieur Kettering did not murder his wife?"

"Are you mad, Monsieur Poirot?"

It was Van Aldin who spoke.

"No," said Poirot, "I am not mad. I am eccentric, perhaps—at least certain people say so; but as regards my profession, I am very much, as one says, 'all there.' I ask you, Monsieur Van Aldin, whether you would be glad or sorry if what I tell you should be the case?"

Van Aldin stared at him.

"Naturally I should be glad," he said at last. "Is this an exercise in suppositions, Monsieur Poirot, or are there any facts behind it?"