For this François Paul, whom the sergeant thus respectfully addressed as Inspector, was no other than an officer of the secret police who had been sent down to Beaulieu the day before from head-quarters in Paris. He was no ordinary officer. As if M. Havard had had an idea that the Langrune affair would prove to be puzzling and complicated, he had singled out the very best of his detectives, the most expert inspector of them all--Juve. It was Juve who for the last forty-eight hours had been prowling about the château of Beaulieu disguised as a tramp, and had had himself arrested with Bouzille that he might prosecute his own investigations without raising the slightest suspicion as to his real identity. Juve made a face expressive of his vexation at the over-deferential attitude of the sergeant. "Do pay attention!" he said low. "We are being watched. If I must go back with you, pretend to arrest me. Slip the handcuffs on me!" "I beg your pardon, Inspector: I don't like to," the gendarme answered. For all reply, Juve turned his back on him. "Look here," he said, "I will take a step or two forward as if I meant to run away; then you must put your hand on my shoulder roughly, and I will stumble; when I do, slip the bracelets on." From the mouth of the tunnel the plate-layer, the foreman and the navvies all followed with their eyes the unintelligible conversation passing between the gendarme and the tramp a hundred yards away. Suddenly they saw the man try to get off and the sergeant seize him almost simultaneously. A few minutes later the individual, with his hands linked together in front of him, was obediently descending the steep slope of the embankment, by the gendarme's side, and then the two men disappeared behind a clump of trees. "I understand why that chap was not very keen on getting taken on here," said the foreman. "His conscience was none too easy!" As they walked briskly in the direction of Beaulieu Juve asked the sergeant: "What has happened at the château, then?" "They know who the murderer is, Inspector," the sergeant answered. "Little Mlle. Thérèse----" VI. "FANTÔMAS, IT IS DEATH!" Hurrying back towards the château with the sergeant, Juve ran into M. de Presles outside the park gate. The magistrate had just arrived from Brives in a motor-car which he had commandeered for his personal use during the last few days. "Well," said Juve in his quiet, measured tones, "have you heard the news?" And as the magistrate looked at him in surprise he went on: "I gather from your expression that you have not. Well, sir, if you will kindly fill up a warrant we will arrest M. Charles Rambert."