It was all quite clear to me now. The Dentrys had required an accomplice. And an accomplice is a very dangerous person. If they could get some simple, honest fool, like myself, to believe she was a medium and that she was in reality responsible for the manifestations, all would be safe. The accomplice would not even know that there was any trickery. On the first occasion when I was at Hanford Gardens, Mr. Dentry had not left the house. A front door may shut heavily though no one goes in or out. And I could see that Dentry had brought his hat and gloves into the room instead of leaving them in the hall, with a view to impressing me with the idea that he had not been in the house. Of course he had been in the back room and had entered by the wainscot. There was a reason doubtless for that thick and noiseless carpet. At the next sitting Mrs. Dentry had simply taken the place of her husband. I knew that Dr. Morning had discovered the trick, but I could not make out how he had discovered it. He had removed a couch and examined that particular piece of wainscot with the utmost care, and I am sure that he had been perfectly satisfied with it. In the meantime, what was I to do? Ought I to inform the police, or to write to Mr. Wentworth Holding, or to call on Dr. Morning? Great though my disgust with the Dentrys was, I had a stupid woman’s reluctance to get them into serious trouble. As I was thinking over these things there came a tap at my outer door. Minnie Saxe had gone and I opened the door myself. Mrs. Dentry stood there, looking very nice and fresh and neat. “Have you just a few minutes to spare?” she said. I asked her to come in. “It’s such a disappointment,” she began. “Dr. Morning was quite satisfied--indeed, under his conditions any trickery would have been impossible. But Mr. Holding has developed religious scruples. He won’t go on. So I fear I have no more work of the kind to offer you. In fact, we are leaving for Liverpool to-morrow ourselves. We have heard of an opening there. But I have brought your fee.” She began fumbling with her purse. “I shall not take your money, Mrs. Dentry,” I said. “I know exactly how the swindle is worked. Minnie Saxe, who was once employed by you as caretaker, is at present my servant. And she is a very observant and intelligent child. But there are two things I don’t understand, and I should like you to explain them.” Beyond the fact that she breathed a little quicker, Mrs. Dentry seemed quite unput out. “What are your questions?” she asked. “I have never given you my address. How did you know it?” “My husband followed you home last night. He was afraid of any communication between you and the doctor. He did not recognise Minnie Saxe, nor do I think he knows how much she has found out. And the other question?” “How did Dr. Morning find out? I am sure his examination of the walls of the room told him nothing.”