'There is old Francoise, the housekeeper, she lived for many years with the former owners of the Villa Genevieve. Then there are two young girls, sisters, Denise and Leonie Oulard. Their home is in Merlinville, and they come of most respectable parents. Then there is the chauffeur whom Monsieur Renauld brought over from England with him, but he is away on a holiday. Finally there are Madame Renauld and her son, Monsieur Jack Renauld. He, too, is away from home at present.'

Poirot bowed his head. Hautet spoke: 'Marchaud!'

The sergent de ville appeared.

'Bring in the woman Francoise.'

The man saluted, and disappeared. In a moment or two he returned, escorting the frightened Francoise.

'Your name is Francoise Arrichet?'

'Yes, monsieur.'

'You have been a long time in service at the Villa Genevieve?'

'Eleven years with Madame la Vicomtesse. Then when she sold the villa this spring, I consented to remain on with the English master. Never did I imagine-'

The magistrate cut her short.

'Without doubt, without doubt. Now, Francoise, in this matter of the front door whose business was it to fasten it at night?'

'Mine, monsieur. Always I saw to it myself.'

'And last night?'

'I fastened it as usual.'

'You are sure of that?'

'I swear it by the blessed saints, monsieur.'

'What time would that be?'

'The same time as usual, half past ten, monsieur.'

'What about the rest of the household, had they gone up to bed?'

'Madame had retired some time before. Denise and Leonie went up with me. Monsieur was still in his study.'

'Then, if anyone unfastened the door afterwards, it must have been Monsieur Renauld himself.

Francoise shrugged her broad shoulders. 'What should he do that for? With robbers and assassins passing every minute! A nice idea! Monsieur was not an imbecile. It is not as though he had had to let the lady out-'