But I think that even he is convinced that Mademoiselle Kritchnoff is not a friend of Arsene Lupin." "Oh, well, perhaps she isn't.

But there's no telling," said Guerchard slowly.
"Arsene Lupin ?" cried the Duke.

"Surely you never thought that Mademoiselle Kritchnoff had anything to do with Arsene Lupin ?" "I never thought so," said M.Formery.

"But when one has a fixed idea ...

well, one has a fixed idea." He shrugged his shoulders, and looked at Guerchard with contemptuous eyes.
The Duke laughed, an unaffected ringing laugh, but not a pleasant one: "It's absurd!" he cried.
"There are always those thefts," said Guerchard, with a nettled air.
"You have nothing to go upon," said M.Formery.