For a space there was silence in the room while McKelvie paced the floor, a worried crease between his brows. As for Jones and myself, we looked from the girl to one another in undisguised perplexity.

How was it possible for Lee Darwin, whom we had rescued from the hands of the criminal at Hi Ling's shop, to be the same person who had kept Cora Manning a prisoner? Or had the boy been merely pretending to be unconscious, and the old man had been a confederate in the game which they were playing to trap McKelvie? Yet, the doctor had said that Lee was really ill, and the doctor could not possibly have any motive for lying, since he had been called in by Jones and was a stranger to us. Again, Cora had said that Lee had come to see her just previous to our rescue of her, and at that time I can swear to it that he was upstairs in one of the rooms in McKelvie's house.

Of course there was always the chance that the young man we had saved was not Lee Darwin at all (though who else he could be I had no idea), for I had only seen him once the day of the inquest, and the others had never laid eyes on him before. To counterbalance that hypothesis, however, was the straightforward story he had told, which tallied point for point with Cora's account. There was some deep mystery here which I for one could not fathom.

"My dear child," said McKelvie presently (from his tone one would have judged him old enough to be her father), "are you sure that you did not dream this tale?"

"Dream it? Oh, no, it was too horribly real for me to have dreamt it," she answered, astonished that he should doubt her.

"I was not referring to the treatment you had received, but to Lee Darwin's connection with your incarceration," he explained. "At the time of which you speak, Lee was himself a prisoner in Chinatown. And to-night he is at my home, ill in bed, too ill to have been able to come here at all."

"Lee—a prisoner? Lee—at your house ill? How can that be?" she asked in wondering tones.

"Miss Manning, did you see this man's face so that you could swear to it?" continued McKelvie earnestly.

"No. It was dark when he spoke to me in the little room, and up here the light behind him was always dim. But I heard his voice, Mr. McKelvie. I could swear it was Lee's," she insisted.

"Voices are easily imitated. He did not talk to you for any great length of time and he was careful that you should not see his face too closely. If he had been Lee he would not have cared how much you saw his features." McKelvie laid a hand on the girl's arm, as he added: "I want you to believe that Lee had nothing to do with this affair. On the contrary, he has done his best to protect you, almost giving his life for your sake. Let me tell you his story briefly. He can fill in the details for you later," and he told her of our trip to Hi Ling's shop.

"I'm so glad," she said, raising tear-filled eyes to his face as he ended. "You see I love him still, even though I thought him—all that was bad. May I see him soon?"

"Yes, but I'm going to ask you to remain in this house to-night. You are not strong enough yet to take a journey in the Subway and I have no desire to use the phone to call a taxi. The criminal may have a means of tapping the wire, for all we know. Now, Miss Manning, are you sure he is coming back to-morrow?"

"Yes, he told me he would return to-morrow night. He said he had to get money enough for our trip in case I should go with him, and that a woman always needed plenty of spare cash. Besides, he'd be sure to come, if only to give me my choice. He would not leave me here alive for someone to discover. He made that very plain to me," she returned, with a shudder.

"Very well, then, we will meet him in your place. I'm going to guard you to-night myself, in case he should change his mind and come again unexpectedly. In the meantime, I wish that you, Mr. Davies, would spend the night at my house to protect Lee. And if you will come around to Stuyvesant Square at ten o'clock to-morrow morning, Jones, I'll give you the other details necessary to catch the murderer in his own little trap."

"Do you want a taxi for to-morrow, then?" asked Jones, as we were leaving.

"Yes, send one around about nine o'clock. Tell him to wait at the corner of Dyckman and Broadway. Or, better yet, send one of your own men with the car, in order that there may be no hitch in our plans."

Jones promised and we returned to town via the Subway, and parted company at Union Square. When I reached McKelvie's house I stopped at Lee's room and found that he was awake. He called to me to know whether I had any news, so I told him the latest developments, watching his face while I talked. He listened eagerly to what I had to say, was unaffectedly glad of the girl's release and thankful to learn that she was safe. His face darkened when I spoke of the impersonation, and he was just as much at a loss as myself to account for it.

When I turned in I had come to one conclusion at least, and that was that Lee had had no hand in the murder, either as principal or as confederate.

At ten o'clock the next morning Jones put in an appearance, but McKelvie had not yet returned, so we occupied ourselves with a discussion of the events of the previous night. Finally we came to the conclusion that Cora Manning in her dazed state had, perhaps, mistaken Dick for Lee, since both were more or less of a height. But in that event, Dick purposely misled her. Why? What reason could he have for such an action, unless indeed, his love for her, coupled with the crime committed in a moment of passionate anger against the man who had injured him, had turned his brain.

When McKelvie arrived he brought Cora Manning with him and asked me to conduct her to Lee. I helped her up the stairs and to the room where Lee was sitting, and as he rose and held out his arms to her I turned away and went back downstairs, where McKelvie was issuing his orders to Jones.

"I want you to bring three men to the house with you, Jones. Be out there at five o'clock and get Mason to let you in the back way. Wait in the passageway for me. Get Grenville to accompany you. Tell him it's important."

"You think you'll be able to catch him?" inquired Jones, as he picked up his hat.

"He has no suspicion of our visit last night. Our rescue of Lee, although in a measure it proves that Mrs. Darwin had nothing to do with the crime, does not in his opinion help us to locate Cora. He only kept Lee at Hi Ling's to prevent him from giving evidence in Mrs. Darwin's behalf. He will come to the house to-night without the least suspicion that there will be anyone there to greet him as he deserves," and McKelvie laughed.

"Then you know who he is?" I inquired, as Jones left the house.

"I still suspect. I shall not know positively until to-night. And now I'm going to get some sleep. Then we will go over to the Darwin bank. I have a mind to see whether that one hundred and fifty thousand dollars is still there."

Taking advantage of the respite, I went back to my own apartments for luncheon, and returned to Stuyvesant Square in my car. Evidently in McKelvie's mind Cunningham was still under suspicion, yet I could hardly credit that it was Cunningham who had kept the girl a prisoner. He did not resemble Lee.

When we arrived at the bank Mr. Trenton turned us over to Raines, who conducted us to the safe-deposit vault.

"Do you know whether Cunningham was in to-day?" asked McKelvie.

"No, I don't. One of the tellers might be able to tell you," responded Raines.

"Never mind. The strong box will tell me all I want to know," McKelvie answered.

We approached Cunningham's box and Raines inserted his key in the lock. As he pulled it open I leaned closer to look at the interior. Then I gave an exclamation of astonishment. The box was empty! The one hundred and fifty thousand dollars in bills was gone!

It was two days ago that we had interviewed Cunningham and he did not then contemplate removing the money from the bank. What had occasioned this sudden need for so much cash? I could think of only one reason. His must be the master mind that had conceived the crime and struck the blow against Darwin, even though he had since hired confederates to aid him in his scheme of holding Cora, as he had done in the case of Lee.

I spoke my thought to McKelvie as we drove back to his home, but he shook his head.

"The criminal had no confederates to aid him against the girl. He has played a lone hand all through with one exception, that is, in the case of Lee."

"Then why did he remove that money from the bank?" I asked.

"Perhaps he is going on that trip he was telling us about the other night," responded McKelvie cynically, and I knew by his tone that he himself did not believe any such thing.

"A trip which will end before it has begun, since it's very apparent his only reason for flight must be that he killed Philip Darwin," I said with a laugh.

"Oh, no," responded McKelvie, coolly, "he is clever and unprincipled, and all kinds of a blackguard, and I wouldn't be at all surprised if he had a couple of murders to his name, but this I do know. He did not murder Philip Darwin."