They got out at a small country station. The shadows of the hot twilight were merging into darkness. A few minutes walking brought them to an inn, at which Monsieur Dupont demanded, and obtained, a conveyance.

For half an hour they drove through the heavily scented air of the country. Scarcely a word was spoken until they reached another village. There, Monsieur Dupont requested the inspector to alight and they proceeded on foot.

The red rear-light of a motor-car appeared at the turn of a corner. Monsieur Dupont drew a deep breath.

"Le bon Dieu be thanked!" he muttered.

The car was stationary and empty. Monsieur Dupont laid a hand on the radiator.

"It is hot," he said. "They have only been here a few minutes. Do not make a sound."

He opened a gate. The long low shape of a house was in front of them. They stood still, listening. There was no sound, no light.

"To the back," Monsieur Dupont whispered.