“It is really remarkable, Velmont, what a close resemblance you bear to Arsène Lupin!”  
“How do you know?”
 
“Oh! like everyone else, from photographs, no two of which are alike, but each of them leaves the impression of a face.... something like yours.”
 
Horace Velmont displayed some vexation.
 
“Quite so, my dear Devanne. And, believe me, you are not the first one who has noticed it.”
 
“It is so striking,” persisted Devanne, “that if you had not been recommended to me by my cousin d’Estevan, and if you were not the celebrated artist whose beautiful marine views I so admire, I have no doubt I should have warned the police of your presence in Dieppe.”
 
This sally was greeted with an outburst of laughter. The large dining-hall of the Château de Thibermesnil contained on this occasion, besides Velmont, the following guests: Father Gélis, the parish priest, and a dozen officers whose regiments were quartered in the vicinity and who had accepted the invitation of the banker Georges Devanne and his mother. One of the officers then remarked:
 
“I understand that an exact description of Arsène Lupin has been furnished to all the police along this coast since his daring exploit on the Paris-Havre express.”
 
“I suppose so,” said Devanne. “That was three months ago; and a week later, I made the acquaintance of our friend Velmont at the casino, and, since then, he has honored me with several visits—an agreeable preamble to a more serious visit that he will pay me one of these days—or, rather, one of these nights.”
 
This speech evoked another round of laughter, and the guests then passed into the ancient “Hall of the Guards,” a vast room with a high ceiling, which occupied the entire lower part of the Tour Guillaume—William’s Tower—and wherein Georges Devanne had collected the incomparable treasures which the lords of Thibermesnil had accumulated through many centuries. It contained ancient chests, credences, andirons and chandeliers. The stone walls were overhung with magnificent tapestries. The deep embrasures of the four windows were furnished with benches, and the Gothic windows were composed of small panes of colored glass set in a leaden frame. Between the door and the window to the left stood an immense bookcase of Renaissance style, on the pediment of which, in letters of gold, was the word “Thibermesnil,” and, below it, the proud family device: “Fais ce que veulx” (Do what thou wishest). When the guests had lighted their cigars, Devanne resumed the conversation.
 
“And remember, Velmont, you have no time to lose; in fact, to-night is the last chance you will have.”
 
“How so?” asked the painter, who appeared to regard the affair as a joke. Devanne was about to reply, when his mother mentioned to him to keep silent, but the excitement of the occasion and a desire to interest his guests urged him to speak.
 
“Bah!” he murmured. “I can tell it now. It won’t do any harm.”
 
The guests drew closer, and he commenced to speak with the satisfied air of a man who has an important announcement to make.
 
“To-morrow afternoon at four o’clock, Sherlock Holmes, the famous English detective, for whom such a thing as mystery does not exist; Sherlock Holmes, the most remarkable solver of enigmas the world has ever known, that marvelous man who would seem to be the creation of a romantic novelist—Sherlock Holmes will be my guest!”
 
Immediately, Devanne was the target of numerous eager questions. “Is Sherlock Holmes really coming?” “Is it so serious as that?” “Is Arsène Lupin really in this neighborhood?”
 
“Arsène Lupin and his band are not far away. Besides the robbery of the Baron Cahorn, he is credited with the thefts at Montigny, Gruchet and Crasville.”
 
“Has he sent you a warning, as he did to Baron Cahorn?”
 
“No,” replied Devanne, “he can’t work the same trick twice.”
 
“What then?”
 
“I will show you.”
 
He rose, and pointing to a small empty space between the two enormous folios on one of the shelves of the bookcase, he said:
 
“There used to be a book there—a book of the sixteenth century entitled ‘Chronique de Thibermesnil,’ which contained the history of the castle since its construction by Duke Rollo on the site of a former feudal fortress. There were three engraved plates in the book; one of which was a general view of the whole estate; another, the plan of the buildings; and the third—I call your attention to it, particularly—the third was the sketch of a subterranean passage, an entrance to which is outside the first line of ramparts, while the other end of the passage is here, in this very room. Well, that book disappeared a month ago.”
 
“The deuce!” said Velmont, “that looks bad. But it doesn’t seem to be a sufficient reason for sending for Sherlock Holmes.”
 
“Certainly, that was not sufficient in itself, but another incident happened that gives the disappearance of the book a special significance. There was another copy of this book in the National Library at Paris, and the two books differed in certain details relating to the subterranean passage; for instance, each of them contained drawings and annotations, not printed, but written in ink and more or less effaced. I knew those facts, and I knew that the exact location of the passage could be determined only by a comparison of the two books. Now, the day after my book disappeared, the book was called for in the National Library by a reader who carried it away, and no one knows how the theft was effected.”
 
The guests uttered many exclamations of surprise.
 
“Certainly, the affair looks serious,” said one.
 
“Well, the police investigated the matter, and, as usual, discovered no clue whatever.”
 
“They never do, when Arsène Lupin is concerned in it.”
 
“Exactly; and so I decided to ask the assistance of Sherlock Holmes, who replied that he was ready and anxious to enter the lists with Arsène Lupin.”
 
“What glory for Arsène Lupin!” said Velmont. “But if our national thief, as they call him, has no evil designs on your castle, Sherlock Holmes will have his trip in vain.”
 
“There are other things that will interest him, such as the discovery of the subterranean passage.”
 
“But you told us that one end of the passage was outside the ramparts and the other was in this very room!”
 
“Yes, but in what part of the room? The line which represents the passage on the charts ends here, with a small circle marked with the letters ‘T.G.,’ which no doubt stand for ‘Tour Guillaume.’ But the tower is round, and who can tell the exact spot at which the passage touches the tower?”
 
Devanne lighted a second cigar and poured himself a glass of Benedictine. His guests pressed him with questions and he was pleased to observe the interest that his remarks had created. The he continued:
 
“The secret is lost. No one knows it. The legend is to the effect that the former lords of the castle transmitted the secret from father to son on their deathbeds, until Geoffroy, the last of the race, was beheaded during the Revolution in his nineteenth year.”
 
“That is over a century ago. Surely, someone has looked for it since that time?”
 
“Yes, but they failed to find it. After I purchased the castle, I made a diligent search for it, but without success. You must remember that this tower is surrounded by water and connected with the castle only by a bridge; consequently, the passage must be underneath the old moat. The plan that was in the book in the National Library showed a series of stairs with a total of forty-eight steps, which indicates a depth of more than ten meters. You see, the mystery lies within the walls of this room, and yet I dislike to tear them down.”
 
“Is there nothing to show where it is?”
 
“Nothing.”
 
“Mon. Devanne, we should turn our attention to the two quotations,” suggested Father Gélis.
 
“Oh!” exclaimed Mon. Devanne, laughing, “our worthy father is fond of reading memoirs and delving into the musty archives of the castle. Everything relating to Thibermesnil interests him greatly. But the quotations that he mentions only serve to complicate the mystery. He has read somewhere that two kings of France have known the key to the puzzle.”
 
“Two kings of France! Who were they?”
 
“Henry the Fourth and Louis the Sixteenth. And the legend runs like this: On the eve of the battle of Arques, Henry the Fourth spent the night in this castle. At eleven o’clock in the evening, Louise de Tancarville, the prettiest woman in Normandy, was brought into the castle through the subterranean passage by Duke Edgard, who, at the same time, informed the king of the secret passage. Afterward, the king confided the secret to his minister Sully, who, in turn, relates the story in his book, “Royales Economies d’Etat,” without making any comment upon it, but linking with it this incomprehensible sentence: ‘Turn one eye on the bee that shakes, the other eye will lead to God!’”
 
After a brief silence, Velmont laughed and said:
 
“Certainly, it doesn’t throw a dazzling light upon the subject.”
 
“No; but Father Gélis claims that Sully concealed the key to the mystery in this strange sentence in order to keep the secret from the secretaries to whom he dictated his memoirs.”
 
“That is an ingenious theory,” said Velmont.
 
“Yes, and it may be nothing more; I cannot see that it throws any light on the mysterious riddle.”
 
“And was it also to receive the visit of a lady that Louis the Sixteenth caused the passage to be opened?”
 
“I don’t know,” said Mon. Devanne. “All I can say is that the king stopped here one night in 1784, and that the famous Iron Casket found in the Louvre contained a paper bearing these words in the king’s own writing: ‘Thibermesnil 3-4-11.’”
 
Horace Velmont laughed heartily, and exclaimed:
 
“At last! And now that we have the magic key, where is the man who can fit it to the invisible lock?”
 
“Laugh as much as you please, monsieur,” said Father Gèlis, “but I am confident the solution is contained in those two sentences, and some day we will find a man able to interpret them.”
 
“Sherlock Holmes is the man,” said Mon. Devanne, “unless Arsène Lupin gets ahead of him. What is your opinion, Velmont?”
 
Velmont arose, placed his hand on Devanne’s shoulder, and declared:
 
“I think that the information furnished by your book and the book of the National Library was deficient in a very important detail which you have now supplied. I thank you for it.”
 
“What is it?”
 
“The missing key. Now that I have it, I can go to work at once,” said Velmont.
 
“Of course; without losing a minute,” said Devanne, smiling.
 
“Not even a second!” replied Velmont. “To-night, before the arrival of Sherlock Holmes, I must plunder your castle.”
 
“You have no time to lose. Oh! by the way, I can drive you over this evening.”
 
“To Dieppe?”
 
“Yes. I am going to meet Monsieur and Madame d’Androl and a young lady of their acquaintance who are to arrive by the midnight train.”
 
Then addressing the officers, Devanne added:
 
“Gentlemen, I shall expect to see all of you at breakfast to-morrow.”
 
The invitation was accepted. The company dispersed, and a few moments later Devanne and Velmont were speeding toward Dieppe in an automobile. Devanne dropped the artist in front of the Casino, and proceeded to the railway station. At twelve o’clock his friends alighted from the train. A half hour later the automobile was at the entrance to the castle. At one o’clock, after a light supper, they retired. The lights were extinguished, and the castle was enveloped in the darkness and silence of the night.
 
The moon appeared through a rift in the clouds, and filled the drawing-room with its bright white light. But only for a moment. Then the moon again retired behind its ethereal draperies, and darkness and silence reigned supreme. No sound could be heard, save the monotonous ticking of the clock. It struck two, and then continued its endless repetitions of the seconds. Then, three o’clock.
 
Suddenly, something clicked, like the opening and closing of a signal-disc that warns the passing train. A thin stream of light flashed to every corner of the room, like an arrow that leaves behind it a trail of light. It shot forth from the central fluting of a column that supported the pediment of the bookcase. It rested for a moment on the panel opposite like a glittering circle of burnished silver, then flashed in all directions like a guilty eye that scrutinizes every shadow. It disappeared for a short time, but burst forth again as a whole section of the bookcase revolved on a pivot and disclosed a large opening like a vault.
 
A man entered, carrying an electric lantern. He was followed by a second man, who carried a coil of rope and various tools. The leader inspected the room, listened a moment, and said:
 
“Call the others.”
 
Then eight men, stout fellows with resolute faces, entered the room, and immediately commenced to remove the furnishings. Arsène Lupin passed quickly from one piece of furniture to another, examined each, and, according to its size or artistic value, he directed his men to take it or leave it. If ordered to be taken, it was carried to the gaping mouth of the tunnel, and ruthlessly thrust into the bowels of the earth. Such was the fate of six armchairs, six small Louis XV chairs, a quantity of Aubusson tapestries, some candelabra, paintings by Fragonard and Nattier, a bust by Houdon, and some statuettes. Sometimes, Lupin would linger before a beautiful chest or a superb picture, and sigh:
 
“That is too heavy.... too large.... what a pity!”
 
In forty minutes the room was dismantled; and it had been accomplished in such an orderly manner and with as little noise as if the various articles had been packed and wadded for the occasion.
 
Lupin said to the last man who departed by way of the tunnel:
 
“You need not come back. You understand, that as soon as the auto-van is loaded, you are to proceed to the grange at Roquefort.”
 
“But you, patron?”
 
“Leave me the motor-cycle.”
 
When the man had disappeared, Arsène Lupin pushed the section of the bookcase back into its place, carefully effaced the traces of the men’s footsteps, raised a portière, and entered a gallery, which was the only means of communication between the tower and the castle. In the center of this gallery there was a glass cabinet which had attracted Lupin’s attentions. It contained a valuable collection of watches, snuff-boxes, rings, chatelaines and miniatures of rare and beautiful workmanship. He forced the lock with a small jimmy, and experienced a great pleasure in handling those gold and silver ornaments, those exquisite and delicate works of art.
 
He carried a large linen bag, specially prepared for the removal of such knick-knacks. He filled it. Then he filled the pockets of his coat, waistcoat and trousers. And he was just placing over his left arm a number of pearl reticules when he heard a slight sound. He listened. No, he was not deceived. The noise continued. Then he remembered that, at one end of the gallery, there was a stairway leading to an unoccupied apartment, but which was probably occupied that night by the young lady whom Mon. Devanne had brought from Dieppe with his other visitors.
 
Immediately he extinguished his lantern, and had scarcely gained the friendly shelter of a window-embrasure, when the door at the top of the stairway was opened and a feeble light illuminated the gallery. He could feel—for, concealed by a curtain, he could not see—that a woman was cautiously descending the upper steps of the stairs. He hoped she would come no closer. Yet, she continued to descend, and even advanced some distance into the room. Then she uttered a faint cry. No doubt she had discovered the broken and dismantled cabinet.
 
She advanced again. Now he could smell the perfume, and hear the throbbing of her heart as she drew closer to the window where he was concealed. She passed so close that her skirt brushed against the window-curtain, and Lupin felt that she suspected the presence of another, behind her, in the shadow, within reach of her hand. He thought: “She is afraid. She will go away.” But she did not go. The candle, that she carried in her trembling hand, grew brighter. She turned, hesitated a moment, appeared to listen, then suddenly drew aside the curtain.
 
They stood face to face. Arsène was astounded. He murmured, involuntarily:
 
“You—you—mademoiselle.”
 
It was Miss Nelly. Miss Nelly! his fellow passenger on the transatlantic steamer, who had been the subject of his dreams on that memorable voyage, who had been a witness to his arrest, and who, rather than betray him, had dropped into the water the Kodak in which he had concealed the bank-notes and diamonds. Miss Nelly! that charming creature, the memory of whose face had sometimes cheered, sometimes saddened the long hours of imprisonment.
 
It was such an unexpected encounter that brought them face to face in that castle at that hour of the night, that they could not move, nor utter a word; they were amazed, hypnotized, each at the sudden apparition of the other. Trembling with emotion, Miss Nelly staggered to a seat. He remained standing in front of her.
 
Gradually, he realized the situation and conceived the impression he must have produced at that moment with his arms laden with knick-knacks, and his pockets and a linen sack overflowing with plunder. He was overcome with confusion, and he actually blushed to find himself in the position of a thief caught in the act. To her, henceforth, he was a thief, a man who puts his hand in another’s pocket, who steals into houses and robs people while they sleep.
 
A watch fell upon the floor; then another. These were followed by other articles which slipped from his grasp one by one. Then, actuated by a sudden decision, he dropped the other articles into an armchair, emptied his pockets and unpacked his sack. He felt very uncomfortable in Nelly’s presence, and stepped toward her with the intention of speaking to her, but she shuddered, rose quickly and fled toward the salon. The portière closed behind her. He followed her. She was standing trembling and amazed at the sight of the devastated room. He said to her, at once:
 
“To-morrow, at three o’clock, everything will be returned. The furniture will be brought back.”
 
She made no reply, so he repeated:
 
“I promise it. To-morrow, at three o’clock. Nothing in the world could induce me to break that promise....To-morrow, at three o’clock.”
 
Then followed a long silence that he dared not break, whilst the agitation of the young girl caused him a feeling of genuine regret. Quietly, without a word, he turned away, thinking: “I hope she will go away. I can’t endure her presence.” But the young girl suddenly spoke, and stammered:
 
“Listen.... footsteps....I hear someone....”
 
He looked at her with astonishment. She seemed to be overwhelmed by the thought of approaching peril.
 
“I don’t hear anything,” he said.
 
“But you must go—you must escape!”
 
“Why should I go?”
 
“Because—you must. Oh! do not remain here another minute. Go!”
 
She ran, quickly, to the door leading to the gallery and listened. No, there was no one there. Perhaps the noise was outside. She waited a moment, then returned reassured.
 
But Arsène Lupin had disappeared.
 
As soon as Mon. Devanne was informed of the pillage of his castle, he said to himself: It was Velmont who did it, and Velmont is Arsène Lupin. That theory explained everything, and there was no other plausible explanation. And yet the idea seemed preposterous. It was ridiculous to suppose that Velmont was anyone else than Velmont, the famous artist, and club-fellow of his cousin d’Estevan. So, when the captain of the gendarmes arrived to investigate the affair, Devanne did not even think of mentioning his absurd theory.
 
Throughout the forenoon there was a lively commotion at the castle. The gendarmes, the local police, the chief of police from Dieppe, the villagers, all circulated to and fro in the halls, examining every nook and corner that was open to their inspection. The approach of the maneuvering troops, the rattling fire of the musketry, added to the picturesque character of the scene.
 
The preliminary search furnished no clue. Neither the doors nor windows showed any signs of having been disturbed. Consequently, the removal of the goods must have been effected by means of the secret passage. Yet, there were no indications of footsteps on the floor, nor any unusual marks upon the walls.
 
Their investigations revealed, however, one curious fact that denoted the whimsical character of Arsène Lupin: the famous Chronique of the sixteenth century had been restored to its accustomed place in the library and, beside it, there was a similar book, which was none other than the volume stolen from the National Library.
 
At eleven o’clock the military officers arrived. Devanne welcomed them with his usual gayety; for, no matter how much chagrin he might suffer from the loss of his artistic treasures, his great wealth enabled him to bear his loss philosophically. His guests, Monsieur and Madame d’Androl and Miss Nelly, were introduced; and it was then noticed that one of the expected guests had not arrived. It was Horace Velmont. Would he come? His absence had awakened the suspicions of Mon. Devanne. But at twelve o’clock he arrived. Devanne exclaimed:
 
“Ah! here you are!”
 
“Why, am I not punctual?” asked Velmont.
 
“Yes, and I am surprised that you are.... after such a busy night! I suppose you know the news?”
 
“What news?”
 
“You have robbed the castle.”
 
“Nonsense!” exclaimed Velmont, smiling.
 
“Exactly as I predicted. But, first escort Miss Underdown to the dining-room. Mademoiselle, allow me—”
 
He stopped, as he remarked the extreme agitation of the young girl. Then, recalling the incident, he said:
 
“Ah! of course, you met Arsène Lupin on the steamer, before his arrest, and you are astonished at the resemblance. Is that it?”
 
She did not reply. Velmont stood before her, smiling. He bowed. She took his proffered arm. He escorted her to her place, and took his seat opposite her. During the breakfast, the conversation related exclusively to Arsène Lupin, the stolen goods, the secret passage, and Sherlock Holmes. It was only at the close of the repast, when the conversation had drifted to other subjects, that Velmont took any part in it. Then he was, by turns, amusing and grave, talkative and pensive. And all his remarks seemed to be directed to the young girl. But she, quite absorbed, did not appear to hear them.
 
Coffee was served on the terrace overlooking the court of honor and the flower garden in front of the principal façade. The regimental band played on the lawn, and scores of soldiers and peasants wandered through the park.
 
Miss Nelly had not forgotten, for one moment, Lupin’s solemn promise: “To-morrow, at three o’clock, everything will be returned.”
 
At three o’clock! And the hands of the great clock in the right wing of the castle now marked twenty minutes to three. In spite of herself, her eyes wandered to the ............