He turned to Juanita, and nodded. She left the room.

"The situation, as I understand it," I replied, "is that Midwinter"—I had a curious reluctance in pronouncing the name aloud—"is either concealed here in the City or has made his escape. If he is here, we shall know before to-morrow morning, shall we not?"

"Precisely. I have spent the last hour in going over the plans of the City with the chiefs of the staff. We have divided up the two stages into small sections, and even while I am talking to you the search has begun. The orders are to shoot at sight, to kill that man with less compunction than one would kill a mad dog. If he is really here, he cannot possibly escape."

"Very well, then," I said, "let us turn our attention to the other possibility. Assuming that he has got away, I think we may safely say that the danger is very much lessened."

"While we remain here in the City—yes," Morse agreed.

"And you are determined to do that?"

He took the cigar he had been smoking from his lips, and his hand shook a little. "Think what you like of me," he said, "but remember that there is Juanita. I say to you, Kirby, that if I never descend to the world again alive, I must stay here until Mark Antony Midwinter is dead."

Well, I had already made up my mind on this point. "I think you are quite right," I told him. "Still, he will not make a second appearance in the City. You can treble your precautions. He must be attacked down in the world."

Then a thought struck me for the first time. "But how," I said, "did he and Zorilla ever come here in the first instance? Treachery among the staff? It is the only explanation."

Pu-Yi shook his head. "You may put that out of your mind, Sir Thomas," he said. "That is my department. I know what you cannot know about my chosen compatriots."