“Just one word, Miss Fairfield!” Lily’s companion, guide, and mentor, stopped walking.

“Please do not volunteer any information unless you are asked a direct question,” he said gravely. “Even then it is not necessary for you to answer a question unless you wish to do so. I will tell the Commissioner of Police what happened, and I hope—I am not sure, but I think I may say that that will be the end of the matter as far as you are concerned.”

“I suppose I shall have to show the police where I found the body?” asked Lily in a low voice.

“I trust that will not be necessary.”

A few moments later they were standing in a formal-looking sitting-room, on the ground floor of the house to which they had been admitted by a pleasant-looking bonne à tout faire.

After they had waited some minutes the door opened and a tall, thin man, with a napkin tucked in his collar, entered with hand outstretched.

“This is an unexpected pleasure, dear friend! What can I do for you?” he exclaimed. “You have come just too late to share our Sunday lunch. My married daughter, her husband, and her two children have come over from Nice and we have been having something of a festival. Sit down—sit down!”

As he spoke he was measuring Lily with what she felt to be a pair of very sharp eyes.

“I am ashamed to have come on a Sunday,” began M. Popeau.

“Not at all—not at all! I am delighted to see you,” said M. Bouton, “and there are certain things that will not wait. I hope Mademoiselle is not a new victim of the gang of thieves I mentioned to you yesterday? So far they have spared the Hôtel de Paris. But I have a clue—and it will not be long before they are laid by the heels.”