“This is a serious matter, Mademoiselle,” said the detective. “You realise how serious?”

“Certainly I do.”

“That is well,” said Poirot. “Then you understand, Mademoiselle, that no time must be lost. You will, perhaps, accompany us immediately to the office of the Examining Magistrate.”

Mirelle was taken aback. She hesitated, but, as Poirot had foreseen, she had no loophole for escape.

“Very well,” she muttered. “I will fetch a coat.”

Left alone together, Poirot and Knighton exchanged glances.

“It is necessary to act while⁠—how do you say it?⁠—the iron is hot,” murmured Poirot. “She is temperamental; in an hour’s time, maybe, she will repent, and she will wish to draw back. We must prevent that at all costs.”