That was all that could be elicited from Mrs. Halliday. We hurried
back to London, and the following day saw us _en route_ for the
Continent. With rather a rueful smile, Poirot observed:---
"This Big Four, they make me to bestir myself, _mon ami_. I run
up and down, all over the ground, like our old friend 'the human
foxhound.'"
"Perhaps you'll meet him in Paris," I said, knowing that he referred
to a certain Giraud, one of the most trusted detectives of the Sureté,
whom he had met on a previous occasion.