Hugh Trethowen was amazed, puzzled to ascertain the meaning of this extraordinary arrest. Scarcely a word had been spoken since they started, but the detective, Chémerault, who sat opposite, very attentively examined the prisoner’s features, as if trying to read the depths of his soul. Hugh noticed this inquisitorial look, and turned his head towards the window in the vehicle in a movement expressive of resentment.

They had covered the long line of quays at a slow, jogging pace, crossed the Pont Neuf, followed the Quai de l’Horloge, and turning off to the right, and passing a large gateway, stopped before a narrow passage.

“Here we are, m’sieur,” said the chief detective, opening the door and springing out.

“You said that you would take me to the Commissary,” exclaimed Trethowen, aroused from his reflections.

“It is all the same,” replied the detective; “we are here, at the Préfecture of Police.”

Hugh looked through the window, saw the two policemen on guard, the gloomy passage, the high frowning walls which enclosed the place, and threw himself back into the cab. He understood the truth. Instinctively he looked round for means of escape, but saw none.

One of the detectives graciously offered to assist him to alight, but, pushing the man aside impatiently, he got out. Bracing himself up against the emotion that at first overwhelmed him, he passed into the passage with his head erect and a gleam of assurance in his eyes. Chémerault and the man who had followed him from the hotel walked beside him. At the end of the corridor, flanked on both sides by the offices of inspectors and other officials, are the steps which lead to the office of the chief of the criminal investigation service.

“Which way shall I go?” asked Trethowen, pausing at the foot of the narrow, crooked flight, the stone of which is worn by the constant tread of detectives and criminals.

“Straight up; the door is before you on the first floor.”

Hugh mounted the steps. He understood why his companions insisted on walking behind—that their politeness was merely prudence.