There is nothing to be feared on the side of the Seine, where the rock rises sheer from the water.

One Friday in September the postman appeared as usual at the bridge-head, and, in accordance with his daily rule, the baron himself opened the heavy door.

He examined the man as closely as if he had not for years known that good jolly face and those crafty peasant’s eyes. And the man said, with a laugh:

“It’s me all right, monsieur le baron. It’s not another chap in my cap and blouse.”

“One never knows,” muttered Cahorn.

The postman handed him a pile of newspapers. Then he added:

“And now, monsieur le baron, I have something special for you.”

“Something special! What do you mean?”

“A letter… and a registered letter at that!”

Living cut off from everybody, with no friends nor any one that took an interest in him, the baron never received letters; and this suddenly struck him as an ill-omened event which gave him good cause for nervousness. Who was the mysterious correspondent that came to worry him in his retreat?

“I shall want your signature, monsieur le baron.”

He signed the receipt, cursing as he did so. Then he took the letter, waited until the postman had disappeared round the turn of the road, and, after taking a few steps to and fro, leaned against the parapet of the bridge and opened the envelope. It contained a sheet of ruled paper, headed, in writing:

“Prison de la Santé, Paris.”3

He looked at the signature:

“ARSÈNE LUPIN.”

Utterly dumbfounded, he read:

“MONSIEUR LE BARON,—In the gallery that connects your two drawing-rooms there is a picture by Philippe de Champaigne, an excellent piece of work, which I admire greatly. I also like your Rubens pictures and the smaller of your two Watteaus. In the drawing-room on the right I note the Louis XIII. credence-table, the Beauvais tapestries, the Empire stand, signed by Jacob, and the Renaissance chest. In the room on the left the whole of the case of trinkets and miniatures.

“This time I will be satisfied with these objects, which, I think, can be easily turned into cash. I will therefore ask you to have them properly packed, and to send them to my name, carriage paid, to the Gare de Batignolles, on or before this day week, failing which I will myself see to their removal on the night of Wednesday, the 27th instant. In the latter case, as is only fair, I shall not be content with the above-mentioned objects.

“Pray excuse the trouble which I am giving you, and believe me to be

Yours very truly,

“ARSÈNE LUPIN.”

“P.S.—Be sure not to send me the larger of the two Watteaus. Although you paid thirty thousand francs for it at the salesrooms, it is only a copy, the original having been burned under the Directory, by Barras, in one of his orgies. See Garat’s unpublished Memoirs.

“I do not care either to have the Louis XV. chatelaine, which appears to me to be of doubtful authenticity.”

This letter thoroughly upset Baron Cahorn. It would have alarmed him considerably had it been signed by any other hand. But signed by Arsène Lupin!…

He was a regular reader of the newspapers, knew of everything that went on in the way of theft and crime, and had heard all about the exploits of the infernal housebreaker. He was quite aware that Lupin had been arrested in America by his enemy, Ganimard; that he was safely under lock and key; and that the preliminaries to his trial were now being conducted… with great difficulty, no doubt! But he also knew that one could always expect anything of Arsène Lupin. Besides, this precise knowledge of the castle, of the arrangement of the pictures and furniture was a very formidable sign. Who had informed Lupin of things which nobody had ever seen?

The baron raised his eyes and gazed at the frowning outline of the Malaquis, its abrupt pedestal, the deep water that surrounds it. He shrugged his shoulders. No, there was no possible danger. No one in the world could penetrate to the inviolable sanctuary that contained his collections.

No one in the world, perhaps; but Arsène Lupin? Did doors, draw-bridges, walls, so much as exist for Arsène Lupin? Of what use were the most ingeniously contrived obstacles, the most skilful precautions, once that Arsène Lupin had decided to attain a given object?…

That same evening he wrote to the public prosecutor at Rouen. He enclosed the threatening letter, and demanded police protection.

The reply came without delay: the said Arsène Lupin was at that moment a prisoner at the Santé, where he was kept under strict surveillance and not allowed to write. The letter, therefore, could only be the work of a hoaxer. Everything went to prove this: logic, common sense, and the actual facts. However, so as to make quite sure, the letter had been submitted to a handwriting expert, who declared that, notwithstanding certain points of resemblance, it was not in the prisoner’s writing.

“Notwithstanding certain points of resemblance.” The baron saw only these five bewildering words, which he regarded as the confession of a doubt which alone should have been enough to justify the intervention of the police. His fears increased. He read the letter over and over again.