Grace Duvall went to her room, at Dr. Hartmann's, after her husband's departure, her feelings divided between her joy at his success—for she felt that his departure with Seltz meant success—and her sorrow at seeing him leave her, without so much as a single glance. She felt certain that she would hear from him during the course of the afternoon, and after eating her luncheon, sat down to read a book.

The afternoon seemed interminable. When at last she could bear the inaction no longer, she rose, put on her hat, and started down the stairs. As she reached the hall, one of the attendants came up to her. "Someone wishes to speak to you at the telephone, Miss Ellicott," the woman said.

Grace hurried to the 'phone, which was placed in a small recess half-way down the hall. The woman accompanied her, and stood near by as she took up the receiver. Clearly she was listening. Grace determined to speak with caution. It was undoubtedly Richard calling.

When she at last made out that it was the American Minister, Mr. Phelps, who was speaking, she felt a keen sense of disappointment. She learned that he and his wife wished her to come in and dine with them. At first she refused, fearful least by going into Brussels she might miss some word from Richard. Mr. Phelps was insistent. They counted on her. He would not take a denial. The thought occurred to her, momentarily, that possibly Richard had taken this means of communicating with her. The idea seemed far fetched, and yet—she heard Mr. Phelps' voice, urging her to come, and rather half-heartedly she agreed to do so. "The United States Minister, Mr. Phelps, and his wife, have asked me to dine with them to-night," she said to the attendant. "Will you be so good as to have a cab here for me at half-past seven?"

The woman bowed. "Certainly, mademoiselle," she said, and moved aside as Dr. Hartmann came along the hall.

Grace thought that he looked both puzzled and angry. He assumed a pleasant expression as he saw her, however, and when he spoke she knew he had overheard what she had just said. "Dining at the Minister's to-night?" he remarked, as he paused for a moment. "A charming man, Mr. Phelps. I may look in later, myself, and bring you home." He passed on, his face at once resuming the angry scowl which Grace had marked as he approached her.

She returned to her room, and began her toilette for the evening. The small trunk she had brought from Paris contained but a limited wardrobe—she had not expected anything in the way of social engagements, in this work that Monsieur Lefevre had assigned to her. A gown of black satin, however, trimmed with silver, she had put in at the last moment. It was very becoming—Richard had never seen her in it—she hoped he might come to her, before the evening was over. She half-made up her mind to speak to Mr. Phelps about it—to ask him to telephone to the hotels and attempt to locate Richard for her. Then the thought came to her that she had represented herself to the Minister as Miss Ellicott. Clearly it would never do to let Mr. Phelps know that she had deceived him.

She arrived at the house early, and after being introduced to Mrs. Phelps, went to the latter's room to remove her wraps, and to talk over their mutual acquaintances. None of the other guests had as yet arrived. Grace talked to Mrs. Phelps as brightly as she could, but her mind was intent upon Richard, and she wondered when and how she would hear from him.

Duvall, meanwhile, had been engaged in changing his clothes. When he at last put on the white waistcoat of his evening suit, he took up the one he had worn during the day and removed from it the ivory snuff box which had been the cause of his interrupted honeymoon. He glanced at the thing carelessly, before placing it in his waistcoat pocket, and as he did so, he fancied he detected a slight noise in the corridor without. In a moment he had thrown open the door which led to the hall. A man—evidently one of the hotel servants—was just rising from his knees, a small brush in one hand, a dust pan in the other.

Duvall looked at him sharply. The man bowed, smiling in a stupid way, then began to withdraw, explaining that he was cleaning the hall, and hoping that he had not disturbed "monsieur." The detective closed the door, uncertain whether the man had been watching him or not. He remembered Dufrenne's warning, and realized that in going out, alone, this night, he ran some chances of having the snuff box taken from him. Of course, it was unlikely that Dr. Hartmann had any suspicions of him—yet it seemed advisable to put the box in as safe a place as possible, at least until he was once more across the French frontier. Yet where could he put it? To secrete the thing in his room was out of the question. The place might be searched, for all he knew, within half an hour of his leaving it. To conceal it successfully about his person seemed equally impossible. Where, indeed, could he hope to hide an object of this size, so as to defy a search, in case one should be made? His eyes suddenly fell upon the opera hat which he had taken from his portmanteau. He took it up and gazed at it with a smile, then quickly whipped out his knife and began, with great care, to detach the inner lining of the crown for a distance of perhaps three or four inches. Carefully drawing back the lining, he slipped the thin ivory box beneath it, and pushed it back into place. The lining was of heavy black silk, stiffened by the label of the maker which was glued to it. The space between it and the crown was considerable. When Duvall had once more fastened the silk in place with the aid of a needle and thread which he drew from his dressing case, it would have required a very careful inspection, indeed, to have discovered that there was anything unusual about the hat. Even the added weight of the box was not perceptible—its lightness prevented that. When he had completed his task, the detective suddenly threw open the door and glanced into the hall. It was vacant. Evidently he had not been observed.

There were but four guests at the Minister's that night, of whom Duvall and Grace were two. The other two were a Mr. and Mrs. Haddon, friends of Mrs. Phelps, who were making a short stay in the Belgian capital on their way to their home in London.

The little party, with the exception of Duvall, had already assembled in the drawing-room, awaiting his arrival. Grace found the Haddons charming and cultivated people who had traveled all over the world, owing to Mr. Haddon's connection with the English Consular service. Mr. Phelps had told Grace that they were expecting an American, a friend of his, whose name was Brooks, but she did not exhibit much interest in the matter. She was becoming more and more worried about Richard, and wondered if he could, by any possibility, have left Brussels without communicating with her. The thought seemed unbelievable.

Dinner was set for eight. As the hour was striking, the butler announced Mr. Brooks. Grace glanced up carelessly as the latter entered, then her face went white, and she started forward with a glad cry. Mr. Phelps, who was mumbling an introduction, did not, luckily, observe her agitation. Duvall looked at her coolly. "Good-evening, Miss Ellicott," he said, bowing. "I am delighted to meet you."

The shock of the thing almost unnerved her. "Mr. Brooks," she managed to gasp, her face crimson. In a moment she became calmer, as she observed her husband's warning look, and began to chat with him nervously, as though he were the chance acquaintance he pretended to be. In a moment they all were seated about the dinner-table. He had been able to say to her as they left the drawing-room, however, unheard by the others, "I will ask permission to escort you home." She nodded, with a twinkle in her eyes. All her nervousness and anxiety had left her now, and in their place came a delicious feeling of happiness at Richard's presence, and a keen sense of adventure that made the blood tingle through her whole body. "Mr. Brooks!" She laughed inwardly at the thought that no one at the table but themselves knew that they were husband and wife. She proceeded to enter into the spirit of the occasion with huge delight, questioning Mr. Brooks about his business in Brussels with a keen sense of mischief.

It was along toward the middle of dinner that one of the servants came in and handed Mr. Phelps a card. Duvall, engaged for the moment in conversation with Mrs. Haddon, did not perceive it, but Grace, who sat next to their host, experienced a sudden feeling of alarm. She observed the Minister's puzzled face, as he excused himself and left the table, and for an instant she thought of warning Richard. A moment's thought, however, convinced her of the uselessness of the attempt, nor did she indeed know what she could say to him. She remembered Dr. Hartmann's remark, that he might look in at the Minister's after dinner, to which she had attached no importance at the time. Now the thought came to her that the doctor was in the reception-room without, and that his coming, at this time, in the middle of dinner, meant that some disaster was impending.

In a few moments Mr. Phelps reËntered the room, followed by Dr. Hartmann. The latter was in evening clothes, and his face seemed peculiarly forbidding and grim.

"Dr. Hartmann has consented to join us," he said to his wife. "Philippe"—he turned to the butler—"lay another place." Then he proceeded to introduce Hartmann to Mr. and Mrs. Haddon and to Duvall.

The latter looked at the doctor calmly. "I think we have met before, Doctor," he said, in an even voice.

"Quite so." Hartmann's face showed not a trace of emotion of any sort. "I hope your servant is better."

"He's still asleep," laughed the detective, then explained to the others, in a few words, his adventure of the morning. He saw that the Minister was puzzled, but the latter said nothing, at the time, and in a few moments the matter was forgotten. Only Grace showed any signs of alarm—Duvall went calmly on with his dinner as though nothing had happened. He spoke to her only occasionally and then addressed her with the formal politeness of a total stranger.

Dr. Hartmann was observing him intently under cover of a spirited conversation with Mrs. Phelps. It was clear to Grace that he could not quite understand why Duvall, or Brooks, as he supposed him to be, was dining here at the Minister's.

It was quite late when the party rose from the table, and, a little while later, Grace, anxious to get away from the place, and be alone with Richard, announced that she must return home. "Mr. Brooks has kindly offered to escort me," she said, quickly, fearful that Dr. Hartmann might suggest that she return with him.

The latter smiled coldly, his eyes fixed on her with a gleam of suspicion. "I think I shall be going myself," he said, as he took leave of the remainder of the party.

As they reached the sidewalk, Duvall observed the taxicab he had ordered to be in readiness, standing in front of the door. He helped Grace inside, then turned in some hesitation to the chauffeur. He dared not tell the fellow to drive to the railway station, since Hartmann, who stood beside the cab chatting with Grace, would inevitably hear him. He therefore instructed the man to go to Dr. Hartmann's with the intention of countermanding the order a little later, as soon as they had got out of earshot of the house. He threw open the door, entered the cab, and was about to pull the door shut after him when he felt his wrist seized from behind in a powerful grasp, and before he realized what had happened, Dr. Hartmann had stepped into the cab and closed the door. The chauffeur at once started off at a great rate.

"I'm sure, Mr. Brooks," said the doctor, suavely, as he sat down in the forward seat, his right hand still grasping Duvall's wrist, "that you will not mind taking me home with you. It is a long walk, and I fear there are no other taxicabs in sight."

Duvall looked at him sternly, then attempted to draw away his hand. "What do you mean, monsieur," he asked, harshly, "by detaining me in this manner?" He again tried to free his wrist, but the doctor was too strong for him.

Hartmann smiled pleasantly. "I feared, Mr. Brooks," he said, "that you might be tempted to use the revolver which you have in the pocket of your coat." He reached over quickly with his other hand and drew the revolver from the detective's pocket.

Grace, through all this, had said absolutely nothing. She realized how fatal any interruption by herself might be. She did not know of her husband's intention to leave Brussels that night. She had heard him order the chauffeur to drive to the sanatorium. Perhaps he wished her to return there. In that event, it was imperative that Dr. Hartmann should not know that the supposed Mr. Brooks and herself were anything but the most chance acquaintances.

"Doctor," she cried out, "what are you doing?"

"It seems that Dr. Hartmann has suddenly lost his senses, Miss Ellicott," exclaimed Duvall angrily.

"Quite so, my friend," said the doctor, sarcastically. "Just as our poor friend Seltz lost his. Don't try anything like that," he snarled, suddenly, as Duvall attempted to release his arm with a sudden twist. "I have a few questions I desire to ask you, Mr. Brooks."

"Questions? What are they?"

"I cannot possibly ask them here, in the presence of Miss Ellicott. Perhaps you will oblige me by stepping into my office for a few moments when we arrive at our destination."

"I can spare you five minutes," said Duvall, sullenly. He could not help remembering Dufrenne's advice, and regretted bitterly that he had not followed it. He had been prepared for almost any contingency. As he left the Minister's house, his hand clutched a revolver in the pocket of his coat. There seemed no way in which Hartmann could prevent him from taking Grace to the railway station. He felt so sure of this that he became overconfident. One moment only had he been off guard—the moment when, with his back to Hartmann, he had stepped into the cab. And the latter, seizing upon that instant's slip, had turned the tables upon him so completely that he cursed himself in his chagrin. Here he was, headed for Dr. Hartmann's house, on the outskirts of the town. Once there, the latter's attendants could easily overpower him and carry him into the place helpless. There seemed no possible means of escape. He determined to brazen the matter out, and meet Hartmann on his own ground. Resistance would at this juncture be useless. He congratulated himself that Grace had, by her cleverness, not shown her hand. The doctor evidently did not suspect, at least not very strongly, that she was anything other than she seemed—a patient. He knew he would be searched, and hoped that the place of concealment of the snuff box would defy even Hartmann. After that, he would demand his release, and rely upon Mr. Phelps to get it for him.

He lifted his head and saw that they were at the house. Without loosening his hold upon Duvall's arm, the doctor called to the chauffeur, "Ring the bell." The latter did so. In a moment, a servant appeared. "Send Max and Rudolph here," cried Hartmann, and presently two husky young Germans came out of the house. Hartmann spoke a few quick words to them in their own language and they ranged themselves on either side of the cab door. Then the doctor threw it open, and released the detective's wrist. "Get out, if you please, Mr. Brooks," he said, with a sardonic smile.