"Oh, easily! Lupin has placed two of his accomplices with Pierre Leduc, to watch him and defend him. Now these accomplices are two of my own detectives, two brothers whom I employ in the greatest secrecy and who will hand him over to me at the first opportunity!"

"Well done you! So that ..."

"So that, as Pierre Leduc, we may say, is the central point of the efforts of all those who are trying to solve the famous Kesselbach secret, I shall, sooner or later, through Pierre Leduc, catch, first, the author of the treble murder, because that miscreant substituted himself for Mr. Kesselbach in the accomplishment of an immense scheme and because Mr. Kesselbach had to find Pierre Leduc in order to be able to accomplish that scheme; and, secondly, Arsene Lupin, because Arsene Lupin is pursuing the same object."

"Splendid! Pierre Leduc is the bait which you are throwing to the enemy."

"And the fish is biting, Monsieur le President. I have just had word that a suspicious person was seen, a short time ago, prowling round the little villa where Pierre Leduc is living under the protection of my officers. I shall be on the spot in four hours."

"And the third trump, Lenormand?"

"Monsieur le President, a letter arrived yesterday, addressed to Mr.

Rudolf Kesselbach, which I intercepted... ."

"Intercepted, eh? You're getting on!"

"Yes, I intercepted it, opened it and kept it for myself. Here it is. It is dated two months back. It bears the Capetown postmark and contains these words: 'My dear Rudolf, I shall be in Paris on the 1st of June and in just as wretched a plight as when you came to my assistance. But I have great hopes of this Pierre Leduc affair of which I told you. What a strange story it is! Have you found the man I mean? Where do we stand? I am most anxious to know.' The letter is signed, 'Steinweg.' The first of June," continued M. Lenormand, "is to-day. I have ordered one of my inspectors to hunt me out this Steinweg. I have no doubt that he will succeed."

"Nor I, no doubt at all," cried Valenglay, rising from his chair, "and I make you every apology, my dear Lenormand, and my humble confession: I was on the point of letting you slide ... for good and all! To-morrow I was expecting the prefect of police and M. Weber."

"I knew that, Monsieur le President."

"Impossible!"

"But for that, should I have put myself out? You now see my plan of campaign. On the one side, I am setting traps in which the murderer will be caught sooner or later. Pierre Leduc or Steinweg will deliver him into my hands. On the other side, I am on Arsene Lupin's heels. Two of his agents are in my pay and he believes them to be his most devoted helpers. In addition to this, he is working for me, because he is pursuing the perpetrator of the threefold crime as I am. Only, he imagines that he is dishing me, whereas it is I who am dishing him. So I shall succeed, but on one condition... ."

"What is that?"

"That I am given free scope and allowed to act according to the needs of the moment, without troubling about the public, who are growing impatient, or my superiors, who are intriguing against me."

"I agree."

"In that case, Monsieur le President, in a few days from this I shall be the victor ... or I shall be dead."

At Saint-Cloud. A little villa situated on one of the highest points of the upland, in an unfrequented road.

It was eleven o'clock at night. M. Lenormand left his car at Saint-Cloud and walked cautiously along the road. A shadow appeared.

"Is that you, Gourel?"

"Yes, chief."

"Did you tell the brothers Doudeville that I was coming?"

"Yes, your room is ready, you can go to bed and sleep ... unless they try to carry off Pierre Leduc to-night, which would not surprise me, considering the behavior of the fellow whom the Doudevilles saw."

They walked across the garden, softly entered the house and went up to the first floor. The two brothers, Jean and Jacques Doudeville, were there.

"No news of Prince Sernine?" asked Lenormand.

"No, chief."

"What about Pierre Leduc?"

"He spends the whole day lying flat on his back in his room on the ground-floor, or else in the garden. He never comes up to see us."

"Is he better?"

"Much better. The rest has made a great change in his appearance."

"Is he wholly devoted to Lupin?"

"To Prince Sernine, rather, for he does not suspect that the two are one and the same man. At least, I suppose so. One never knows, with him. He does not speak at all. Oh, he's a queer fish! There's only one person who has the gift of cheering him up, of making him talk and even laugh.

That's a young girl from Garches, to whom Prince Sernine introduced him.

Genevieve Ernemont her name is. She has been here three times already ... she was here to-day." He added, jestingly, "I believe there's a little flirting going on... . It's like his highness Prince Sernine and Mrs. Kesselbach... . It seems he's making eyes at her! ... That devil of a Lupin!"

M. Lenormand did not reply. But it was obvious that all these details, to which he seemed to attach no importance, were noted in the recesses of his memory, to be used whenever he might need to draw the logical inferences from them. He lit a cigar, chewed it without smoking it, lit it again and dropped it.

He asked two or three more questions and then, dressed as he was, threw himself on his bed:

"If the least thing happens, let me be awakened... . If not, I shall sleep through the night... . Go to your posts, all of you."

The others left the room.

An hour passed, two hours.

Suddenly, M. Lenormand felt some one touch him and Gourel said to him:

"Get up, chief; they have opened the gate."

"One man or two?"

"I only saw one ... the moon appeared just then ... he crouched down against a hedge."

"And the brothers Doudeville?"

"I sent them out by the back. They will cut off his retreat when the time comes."

Gourel took M. Lenormand's hand, led him downstairs and then into a little dark room:

"Don't stir, chief; we are in Pierre Leduc's dressing-room. I am opening the door of the recess in which his bed stands... . Don't be afraid ... he has taken his veronal as he does every evening ... nothing can wake him. Come this way... . It's a good hiding-place, isn't it?

... These are the curtains of his bed... . From here you can see the window and the whole side of the room between the window and the bed."

The casement stood open and admitted a vague light, which became very precise at times, when the moon burst through her veil of clouds. The two men did not take their eyes from the empty window-frame, feeling certain that the event which they were awaiting would come from that side.

A slight, creaking noise ...