AT the same hour that Richard Duvall was arranging with Mr. Stapleton his plan for the capture of the kidnappers the following day, Grace was closeted with Monsieur Lefevre, the Prefect of Police, in the latter's library, going over the affair in all its details. The Prefect was speaking, ticking off on his fingers the points in the case as he proceeded.

"First, we have the impossible story of the nurse, Mary Lanahan. She seems to be telling the truth; yet I believe she is lying. In my opinion, she is deeply concerned in the whole matter."

"But what about the attempt to poison her?"

"It is highly probable that she poisoned herself, taking a slight dose only. This would divert suspicion from her."

"I see."

"Then we have the case of Alphonse Valentin, and the mysterious gold-tipped cigarettes. Your husband, Monsieur Duvall, I am informed, has found one of these cigarettes, partly smoked, on the grass at the scene of the crime. This might indicate that Valentin was there, with her, on some occasion, but not necessarily on the day the kidnapping occurred. It might readily have been the day before—or the week before, for that matter."

"I thought of that," remarked Grace, quietly. "It seems to me that Richard attached too much importance to the matter."

"That remains to be seen. Now, supposing Valentin to be concerned, with the nurse, in the plot. He of course does not think, at the start, that the possession of the cigarettes would involve him in the affair, because he does not know that Monsieur Duvall has found the one in the grass. Your husband, however, asks Mary Lanahan what kind of cigarettes Valentin smokes. She at once becomes suspicious, and at the first opportunity warns Valentin, by letter, to destroy them. That shows clearly that they are working together."

"Undoubtedly. But meanwhile the cigarettes are stolen from Valentin's room by a man with a dark beard, who subsequently enters Mr. Stapleton's house. For that, I confess, I can find no explanation."

"Nor I. The destruction of the cigarettes could be of no importance to anyone, except to the kidnappers themselves. It is of course possible that someone else in Mr. Stapleton's house—FranÇois, for instance—is concerned in the plot."

"But the man who took the cigarettes had a black beard, while FranÇois is smooth shaven."

"I know. But it might have been a disguise."

"I do not think so. The man I saw was taller than FranÇois, and not so heavily built."

The Prefect considered the matter for a moment. "You are certain that he entered the Stapleton's house?"

"Absolutely certain. I saw the gate close behind him."

"Then I can only say that, so far, the matter is inexplicable. Now let us come back to Valentin. He claims to be working to capture the kidnappers—in order to clear the nurse, whom he loves."

"That is as I understand it."

"He denies that he smokes, yet offers no explanation of the presence of the cigarettes in his room."

"None. Further, someone sends a note to Valentin, advising him that the writer is suspicious of FranÇois—suggesting that he watch him. Can this mean that FranÇois is in the plot, and they fear he may be weakening—preparing to turn against them?"

"It certainly looks that way."

"I wish I could see one of these famous cigarettes."

Grace laughed suddenly. "Why," she exclaimed, "I have one in my pocketbook. I had quite forgotten it." She opened her purse and took out the slender white cylinder.

Lefevre examined the thing closely. "An Egyptian cigarette of American make," he mused. "Expensive, here in Paris, and rarely used, except by Americans."

"That is true; yet I understand that this man Valentin has lived a great deal in America."

For a moment the Prefect did not reply. Then a puzzled look crossed his face. "This is a woman's cigarette," he exclaimed. "No man would smoke such a thing." He brought his hand down sharply upon his knee. "My girl, it is not impossible that the child was stolen not by a man at all, but by a woman."

"A woman, apparently, that both Valentin and the nurse are trying to shield."

The Prefect sat for a moment buried in thought. Then he glanced at Grace keenly. "It seems to me," he remarked, in a quiet tone, "that we should endeavor to determine whether or not Mrs. Stapleton is in the habit of using cigarettes."

"Mrs. Stapleton!" gasped Grace, in amazement.

"Yes. I confess the idea is a new one, to me; but it may prove of interest."

"But why should the boy's mother wish to kidnap him?"

"I do not know. There is but one point of significance. During the past week my men have, naturally, questioned Mrs. Stapleton closely as to her movements during the past two or three months. They did this, to determine, if possible, whether the criminals were of Paris, or from some other place, where Mrs. Stapleton may have been, with the child, during the past winter. You know these fellows work in bands, and have their regular field of operations."

"I see. And where had she been?""Monte Carlo!" The Prefect uttered the two words significantly.

Grace was quick to grasp his meaning.

"Then you mean that possibly Mrs. Stapleton may have lost large sums at the gambling tables, and, fearing to tell her husband of her losses, has enlisted the services of the nurse, and of her friend Valentin, and spirited the child away for a few weeks, in order to get the sum of one hundred thousand dollars from her husband without his knowledge?"

"It is by no means impossible. I would recommend that you investigate the matter thoroughly. If we find that Mrs. Stapleton uses gold-tipped cigarettes of this variety, it may go far toward a solution of the whole affair."

Grace, remembering Mrs. Stapleton's grief-stricken appearance, felt that the clue was a very slender one, but determined to follow it up, nevertheless.

"Now," went on the Prefect, "we come to the sudden and most unexpected appearance of Valentin, clinging to the rear of the automobile that brought you back to Paris tonight."

"As I have told you, he claims to have clambered into Mr. Stapleton's car.""Driven by FranÇois?"

"Yes."

"And you say the man who drove the car had a black beard—the same man, in fact, who broke into Valentin's room and stole the cigarettes?"

"Yes."

"Then either Valentin is lying, or the man with the black beard is FranÇois. Let us look at his story from both sides. If he is telling the truth, then FranÇois is one of the kidnappers."

"So it would seem. You are having him watched, you say?"

"Yes. My men report that he did leave the house, in Mr. Stapleton's automobile tonight, at about nine o'clock. That would seem to agree with Valentin's story. They also report that he returned about eleven, alone."

"They did not follow him?"

"No. It is impossible to do so, in another car, without arousing his suspicion, and putting him on his guard. We do not wish him to know that he is being watched."

"But Mr. Stapleton must know where he has been—why the car was out."

"Yes. We have questioned him. He says the man reported that the gasolene tank was leaking, and that he ordered him to have it repaired at once."

"And was it repaired?"

The Prefect smiled. "Yes. The car was at a garage in the Boulevard St. Michel from half past nine until half past ten."

Grace fell back, astonished. "Then Valentin is lying!" she cried.

"So it seems; unless, of course, FranÇois took out another car from the garage, while his own was being fixed."

"They would know that at the garage."

"They deny it. But these fellows all hang together. They would think nothing of protecting a brother chauffeur, in the matter of a little joy ride."

"Valentin says nothing about this, in his story."

"He may have omitted it, as an unimportant detail. I mean that he may have slipped into the second car, as he did into the first, without being observed. It was dark of course. He may not have thought it necessary to mention it. All this, of course, is on the assumption that he is telling the truth. Now let us say that he is lying—that the man with the black beard is not FranÇois, but someone else concerned, with Valentin in the plot. What is the purpose of his tale?"

"I cannot imagine. Can you, Monsieur?"

"No, not immediately. The first contradiction, of course, is this. If Valentin and the man with the black beard are working together, why should the latter have broken into his room to get the cigarettes?"

"There seems no sense to it."

"Yet he may have realized the danger of the cigarettes being in Valentin's possession, and instead of trying to warn him simply came and took them away. It is not a particularly plausible explanation; but let us admit it, for the moment, in order to get ahead with our reasoning. Suppose Valentin, the man with the black beard, and Mary Lanahan, the nurse, to be all working together, either with Mrs. Stapleton, or with outside parties. They have the child safely hidden. They abduct you, and send the message to Mr. Stapleton through you. They do not trust you, knowing, no doubt, that you are an agent of my office. They send Valentin along, on the back of the machine, to pretend to be an enemy of theirs trying, like yourself, to recover the child. He thus gets into your confidence. He advises you to report your message from the kidnappers to Mr. Stapleton at once. He questions you, and learns that you do not know the location of the house where the child is hidden. He then offers to show you as nearly as he can where the house is located. If he is in league with the kidnappers, he will take you, and the men whom tomorrow I shall send with you, to some location miles removed from the actual point where the child is concealed, and you will waste the day in a useless search. Decidedly it would be a clever move on their part."

"It certainly would."

"Further, you told this fellow that you had a plan to capture the scoundrels. You are to acquaint him with that plan, tomorrow afternoon. If you do so, he will no doubt get to the telephone on some pretext and warn his comrades of what you intend to do. I strongly recommend that you put no faith in the fellow whatever."

"Still, you would advise trying to locate the house, as he suggests?"

"Yes, we may be wrong about him. We must leave no stone unturned. And now we come to your interview with Mr. Stapleton. You gave him the message, of course. What did he say?""He said that he intended to carry out the instructions I gave him to the letter—pay these fellows their money, and get back the boy."

Monsieur Lefevre uttered an exclamation of anger. "SacrÉ! He must not do that! The stupid fellow! He will spoil everything!"

Grace laughed quietly to herself. "Hardly stupid, Monsieur! The poor man is half mad over the boy's loss. He will do anything, to get him back. I can scarcely blame him."

The Prefect held out his hand. "I beg your pardon, my child. You are right. It is perhaps but natural for him to feel as he does. But there are other things at stake, than the recovery of the child. For Monsieur Stapleton to pay over this huge sum to these criminals, and then to allow them to escape, is not only a grave reflection upon the efficiency of the Paris police, but is an injustice to the public as well. If these men are successful in this attempt, they will make others. Other children will be stolen. I cannot permit it. It must be prevented at all costs. These men must be brought to justice."

"How can you prevent it, Monsieur? Mr. Stapleton is determined."

"That, my child, is the question. I cannot stop Monsieur Stapleton if he wishes to drive out the road to Versailles and toss a hundred thousand dollars into the first automobile that passes him, showing a blue light." He rose and began to walk up and down the room.

"I have a plan, Monsieur," said Grace, quietly.

"What is it, my child?" The Prefect regarded her with an indulgent smile. He was very fond of Grace. He regretted that he had been unable to secure the services of her husband in this case. He knew, from past experience, her cleverness; but he did not believe that in a matter of this sort she would be able to outwit men who were probably among the shrewdest criminals in Paris.

"First," said Grace, "we will have the location pointed out to us by Valentin thoroughly searched."

"Assuredly! It will, however, probably result in nothing. Even if Valentin is telling the truth, these fellows will beyond question have moved the child before now to prepare for the work of tomorrow evening."

"Possibly. At any rate, we will try. After that, I shall want Valentin to drive a motor car for me. He is an accomplished chauffeur.""You will take him into your confidence, then?" asked the Prefect, in some alarm.

"No. I shall tell him nothing, except that he is to drive the car, and where."

"Very well. But be careful. What next?"

Grace leaned over and spoke to the Prefect in low tones for several minutes. He listened to what she said, occasionally smiling, and nodding his head. Presently he brought his hand down sharply upon the table. "Bravo!" he exclaimed. "You were born to be a detective. We will get the kidnappers, the money, and in all probability the child as well. I congratulate you!"

"You think it will work, then?"

"I do not see how it can fail. It is an inspiration. I shall certainly feel very well satisfied indeed, if I can return to Monsieur Stapleton both his child and his money, and at the same time place the kidnappers behind the bars. I could never permit it to be said that the police of Paris would knowingly allow a desperate band of criminals to get away with half a million of francs without lifting a hand to prevent it." He rose and glanced at his watch. "Come, my child. It is after midnight. You have had a long and exciting day. You had better get some rest."Grace rose. "Richard seemed awfully puzzled when he saw me."

"Did he?" The Prefect laughed mischievously. "Really it is a great joke upon him. To be within a step of his own wife, and not to know her!"

Grace seemed scarcely to appreciate the humor of the situation. "I think it's a shame," she said, "Poor Richard. He'll never forgive me. I really think I ought to tell him."

Monsieur Lefevre shook his head. "If you do that, my dear child, everything will be spoiled. He will insist upon your dropping the case at once, and that would certainly not be fair to me."

"But, Monsieur, after all, you really do not need me, with all the clever men you have upon your staff."

"Who knows? Perhaps you may succeed, where they will fail. I have great faith in the intuition of a woman. And already you have advanced the case further in forty-eight hours than my men have done in ten days. It was a chance, I will admit, that these rascals should have chosen you to deliver their demands to Monsieur Stapleton. I confess I do not understand their reasons for doing so. They must have known that besides telling your story to him, you would also tell it to me. It may have been sheer bravado on their part—it is a characteristic, I have noted, in many criminals. They seem to glory in defying the police. These fellows, no doubt, think that they have matters so arranged that capture is impossible. I think we shall give them a little surprise."

He turned to the door, and held it open, allowing Grace to pass into the hall. "Good night, my child," he called out to her, as she began to ascend the stairs. "I think I will smoke one more cigar."

As for Grace, she lay awake a long time, thinking of Richard, of their home in the country, of the happy hours they had spent there—before this unexpected interruption to their honeymoon. It seemed very queer to her, to be lying there, alone. She had not gotten used to it. And somewhere, in this big city, Richard was also sleeping—and she not with him! The excitement of the affair was beginning to die out. The meeting with Richard on the boat, which she had planned when she set out from home, had not materialized. She had postponed this meeting, in her thoughts, until his arrival in Paris, and now—he had come, and still she had not been able so much as to touch his hand. She finally went to sleep, devoutly praying that tomorrow, and the capture of the kidnappers, would mark the end of their needless and cruel separation.