It would have been a comparatively easy matter for the two friends to have slipped out of the house before the cripple came down the stairs accompanied by the young man who called himself Charles Evors. The front door was still open, and there was no one to bar their way. Then it suddenly occurred to Gurdon that by so doing they would betray the secret of the moveable panel which communicated with the house next door.

"It would never do to go away like this," he said, hurriedly. "Besides, it is more than likely that we shall want to use that entrance again. We shall have to run the risk of losing sight of the cripple; anything is better than leaving that panel open for the servants to discover in the morning."

Venner could see for himself at once that there was no help for it, so without any further discussion on the matter, the two men hurried down the stairs, their feet making no noise on the thick carpet, and then they darted through the hole into the house next door. It was only the work of a moment to replace the panel, but hardly had they done so before they heard a confused murmur of voices on the other side. Gurdon pressed his back to the panel until the noise of the voices ceased.

"That was a pretty close call," he said. "Give me the mouldings and I will try to make them secure without any unnecessary noise. I daresay we can get the nails to fit the same holes. Anyway, there must be no hammering, or we shall be pretty sure to rouse the suspicions of the people next door."

It was perhaps fortunate that the mouldings fitted so well, for Gurdon managed to work the nails into the original holes and complete a more or less workmanlike job to his own satisfaction. Certainly, anybody who was not in the secret would never have detected anything wrong with the panels or imagined for a moment that they had been so recently moved.

"That's a good job well done," Venner said.

"Yes, but what do you do it for? In fact, what are you two gentlemen doing here at all?"

The voice came with a startling suddenness. It was an exceedingly clear, melodious voice, yet with a steely ring in it. The two friends wheeled round sharply to find themselves face to face with an exceedingly tall individual, whose length was almost grotesquely added to by the amazing slimness of his figure. In that respect he was not at all unlike the type of human skeleton which one generally expects to find in a travelling circus, or some show of that kind. The man, moreover, was dressed in deep black, which added to his solemnity. He had an exceedingly long, melancholy face, on both sides of which hung a mass of oily-looking black hair; his nose, too, was elongated and thin, and a long drooping moustache concealed his mouth. On the whole his appearance was redeemed from the grotesque by an extraordinary pair of black eyes, which were round and large as those of a Persian cat. Despite the man's exceeding thinness, he conveyed a certain suggestion of strength. At that moment he had a handkerchief between his fingers, and Gurdon could see that his wrists were supple and pliable as if they had been made of india rubber. Gurdon had heard that sort of hands before described as conjurer's hands. As he looked at them he half expected to see the handkerchief disappear and an orange or apple or something of that kind take its place. Then the stranger coolly walked across the hall and turned up another of the lights. He seemed to be perfectly at home, and conveyed a curious impression to the visitors that he expected to find them there.

"I beg to remind you that you have not yet answered my question," he said. "What are you doing here?"

"Let me answer your question with another," Venner said. "Who are you, and what may you be doing here?"

The man smiled in a peculiar fashion. His big black eyes seemed to radiate sparks; they were luminous and full of vivid fury, though, at the same time, the long horse-like face never for a moment lost its look of profound dejection. They might have been eyes gleaming behind a dull, painted mask.

"We will come to that presently," he said. "For the moment the mention of my name must content you. It is just possible that you might have heard the name of Felix Zary."

Venner and Gurdon fairly started. The name of Felix Zary was familiar to them, but only during the last three-quarters of an hour. In fact, that was the name of the man as to whose whereabouts Fenwick had been so anxious to hear. Here was another element in the mystery, which, up to this moment, had not advanced very far towards solution.

"I have heard the name before," Venner said, "but only quite recently—within the last hour, in fact."

"Oh, yes," the stranger said, "I know exactly what you mean. You probably heard it next door when you were listening so intently to the conversation between my friend Charles Le Fenu, the cripple, and that scoundrel who calls himself Fenwick. He is exceedingly anxious to know where I am, though without the smallest intention of benefitting me. Before long, his curiosity will be gratified; but not in the way he thinks."

The latter words came from the speaker's lips with a spitting hiss, such as a cat emits in the presence of a dog. The great round black eyes added intensity to the threat, and rendered the feline simile complete. The prophecy boded ill for Fenwick when at length he and Felix Zary came face to face.

"I see my conjecture is quite right," the stranger went on. "And as to you gentlemen, I have asked your names merely as a matter of courtesy. As a matter of fact I know perfectly well who you are—you are Mr. Gerald Venner and Mr. James Gurdon. But there is one thing I don't know, and that is why you have thrust yourself into this diabolical business. You must be brave men, or absolutely unconscious of the terrible danger you are running. If either of you are friends of Fenwick's—"

"Not for a moment," Venner cried. "You pay us a poor compliment indeed if you take us to be in any way friendly with that scoundrel."

"And yet you are here," Zary went on. "You are spying on the movements of my friend, Le Fenu. You have contrived to obtain possession of the keys of his house for no other purpose. Why?"

Venner paused before he answered the question. He did not recognise the right of this man to put him through a cross-examination. Indeed, it seemed to him, the less he said the better. Perhaps Zary saw something of what was going on in his mind, for his big black eyes smiled, though the dejected visage remained the same.

"I see, you do not trust me," he said. "Perhaps you are right to be cautious. Let me ask you another question, assuring you at the same time that I am the friend of Charles Le Fenu and his sisters, and that if necessary I will lay down my life to save them from trouble. Tell me, Mr. Venner, why are you so interested in saving the girl who passes for Fenwick's daughter from her miserable position? Tell me."

Zary came a step or two closer to Venner and looked down into his face with a searching yearning expression in those magnetic black eyes. The appeal to Venner was irresistible. The truth rose to his lips; it refused to be kept back.

"Because," he said slowly, "because she is my wife."

A great sigh of relief came from Zary.

"I am glad of that," he said. "Exceedingly glad. And yet I had suspected something of the kind. It is good for me to know that I am with friends, and that you two are only actuated by the best motives. For some days now I have had you under close observation. I followed you here to-night; indeed, I was in the house when you removed those panels. As a matter of fact, Mr. Gurdon's first involuntary visit here absolutely ruined a carefully laid plan of mine for getting Mark Fenwick into my hands. But I will tell you later on all about the mystery of the furnished dining-room and how and why the furniture vanished so strangely. When I followed you here to-night I was quite prepared to shoot you both if necessary, but some strange impulse came over me to speak to you and ask you what you were doing. I am rather glad I did, because I should not like to have a tragedy on my hands. Now would you like to come with me as far as my own rooms, where I shall be in a position to throw a little light upon a dark place or two?"

Venner and Gurdon clutched eagerly at the suggestion. Without further words, they passed into the street, and would have walked down the steps had not Zary detained them.

"One moment," he whispered. "Hang back in the shadow of the portico. Don't you see that there are two or three men on the steps of the house next door? Ah, I can catch the tones of that rascal Fenwick. If only that vile scoundrel knew how close to him I was at the present moment! But let us listen. Perhaps we may hear something useful."

It was very still and quiet in the Square now, for the hour was late, and therefore the voices from the portico came clear and distinct to the listeners' ears.

"What is the good of it?" one of the voices said. "Why on earth can't you wait till morning? Le Fenu has got clear away, and there isn't much chance of catching him again in a hurry. It was one of the coolest things I have seen for a long time."

"Oh, he doesn't lack brains, or pluck either," Fenwick said. "I should have been proud of a trick like that myself. I ought to have poisoned him when I had the chance. I ought to have got him out of the way without delay. But it seemed such a safe thing to kidnap him and hide him in his own house, where we could go on with our work without the slightest danger or interruption from those accursed police. And then, when Fate played into our hands and we got hold of Evors as well, it looked as if everything was going our way. How you fools ever contrived to let him get the upper hand of you is more than I can understand."

"It was Jones's fault," another voice growled. "He forgot the drug, and we ran clean out of it. Then, I suppose, we got interested over a game of cards, and one way and another, Evors managed to get six or seven hours' sleep without having any of that stuff inside him. Bless me, if it wasn't all like a dream, guv'nor. There we were, interested in our cards, and before we knew where we were our heads were banged together, and I was lying on the floor thinking that the end of the world had come. That fellow has got the strength of the very devil itself."

"Poor weak creature," Fenwick sneered.

"Weak-minded, perhaps, and easily led," the first speaker said. "But there is not much the matter with him when it comes to fists."

"We can't stop chattering here all night," Fenwick cried. "It is all very well for you men, who don't care so long as you have something to eat and drink. You would be quite satisfied to sit like a lot of hogs in a sty in Le Fenu's house, but he'll certainly be back in the morning with some infernal scheme or other for getting the best of us. Don't you see it is impossible for me any longer to play the part of a tenant of a furnished house, now that the owner of the house is at large again? It is a very fortunate thing, too, in a way, that I can pass all you people off as my servants. Now get away at once and do as I tell you. As for me, I am going to take a cab as far as the old place by the side of the river. In an hour's time I hope to be on my way to Canterbury. Now, you are quite sure you all know what to do? It's confoundedly awkward to have one's plans upset like this, but a clever man always has an alternative scheme on hand, and I've got mine. There, that will do. Be off at once."

"That's all very well, guv'nor," another voice said. "It is easy enough to put the door on the latch and turn out of the crib, leaving it empty, but what about the girl in the white dress? I ain't very scrupulous as a rule, but it seems rather cruel to leave the poor kid behind and she not more than half right in her head."

"Devil fly away with the girl," Fenwick said passionately. "We can pick her up at any time we want to. Besides, I think I can see a way to arrange for her and a method of getting her out of the house within the next hour. It was no bad thing for men who get their living as we do when some genius invented motor cars. Now do go along or we shall never finish."

The little group on the portico steps melted away, and one by one the slouching figures vanished into the darkness. Zary stepped on to the pavement, and proceeded to open the front door of the next house. It yielded to his touch.

"I am glad of this," he said; "and, really, we owe quite a debt of gratitude to the tender-hearted ruffian who was averse to leaving a poor girl in this house all alone. We will spare Fenwick the trouble of any inconvenience so far as she is concerned."

So saying, Zary proceeded to walk up the stairs, turning up the lights as he went. He called the name of Beth softly three or four times, and presently a door opened overhead and a girl in a white dress came out. A pleased smile spread over her face as she looked over the balusters and noted the caller.

"Felix," she said softly, "is it really you? I have been hiding myself in my room because I was terrified, and after Charles had gone those men quarrelled so terribly among themselves! I suppose Charles forgot all about me in the excitement of the moment."

"Oh, no, he didn't, dear one," Zary said very gently. "He would have come back to you in any case. But I am going to take you away from this house where you have been so miserable; I am going to see that you are not molested in the future."

"That is all very well," Venner interposed, "but where can the young lady go? She is quite alone and helpless, and unless you have some reputable female relation—"

"It is not a matter of my relations," Zary smiled. "Miss Beth will go to one who is her natural protector, and one who will watch over her welfare with unceasing care. To put it quite plainly, Miss Beth is going to the Great Empire Hotel, and you are going to take her. To-night she will sleep under the same roof as her sister."

Venner was just a little startled by the suddenness of the proposal, yet, on the whole, the suggestion was an exceedingly natural one, for who was better capable of looking after the unfortunate Beth than her own sister? True, the hour was exceedingly late; but then a huge place like the Great Empire Hotel was practically open night and day, and a request at one o'clock in the morning that a guest in the house should be awakened to receive another guest would be nothing in the way of a novelty.

"Very well," Venner said. "Let her put on her hat and jacket, and she can come with me at once."