"There is a way to fight it," I said quietly. "I am a doctor, not a master of hypnotism, or a man who can discover the reasons behind that hypnotism. But London has its Scotland Yard, and Scotland Yard has a man who is one of my greatest comrades...." She nodded her surrender. As I stepped to the telephone, I heard her murmur, in a weary, troubled voice: "Hypnotism? It is not that. God knows what it is. But it has always happened when I have been alone. One cannot hypnotise through distance...." * * * * * And so, with Margot Vernee's consent, I sought the aid of Inspector Thomas Drake, of Scotland Yard. In half an hour Drake stood beside me, in the quiet of my study. When he had heard Margot's story, he asked a single significant question. It was this: "You say you have a desire to go back to a man who was once intimate with you. Who is he?" Margot looked at him dully. "It is Michael Strange," she said slowly. "Michael Strange, of Paris. A student of science." Drake nodded. Without further questioning he dismissed my patient; and when she had gone, he turned to me. "She did not murder her sweetheart, Dale" he said. "That is evident. Have you any idea who did?" And so I told him of that other young man. Sir John Harmon, who had come to me the night before. When I had finished. Drake stared at me--stared through me--and suddenly turned on his heel. "I shall be back, Dale," he said curtly. "Wait for me!" * * * * * Wait for him! Well, that was Drake's peculiar way of going about things. Impetuous, sudden--until he faced some crisis. Then, in the face of danger, he became a cold, indifferent officer of Scotland Yard. And so I waited. During the twenty-four hours that elapsed before Drake returned to my study, I did my best to diagnose the case before me. First, Sir John Harmon--his visit to the home of Franklin White. Then--the deliberate murder. And, finally, young Margot Vernee, and her confession. It was like the revolving whirl of a pinwheel, this series of events: continuous and mystifying, but without beginning or end. Surely, somewhere in the procession of horrors, there would be a loose end to cling to. Some loose end that would eventually unravel the pinwheel! It was plainly not a medical affair, or at least only remotely so. The thing was in proper hands, then, with Drake following it through. And I had only to wait for his return. He came at last, and closed the door of the room behind him. He stood over me with something of a swagger.