My taking the detective out to Sunnyside raised an unexpected storm of protest from Gertrude and Halsey. I was not prepared for it, and I scarcely knew how to account for it. To me Mr. Jamieson was far less formidable under my eyes where I knew what he was doing, than he was off in the city, twisting circumstances and motives to suit himself and learning what he wished to know, about events at Sunnyside, in some occult way. I was glad enough to have him there, when excitements began to come thick and fast. A new element was about to enter into affairs: Monday, or Tuesday at the latest, would find Doctor Walker back in his green and white house in the village, and Louise’s attitude to him in the immediate future would signify Halsey’s happiness or wretchedness, as it might turn out. Then, too, the return of her mother would mean, of course, that she would have to leave us, and I had become greatly attached to her. From the day Mr. Jamieson came to Sunnyside there was a subtle change in Gertrude’s manner to me. It was elusive, difficult to analyze, but it was there. She was no longer frank with me, although I think her affection never wavered. At the time I laid the change to the fact that I had forbidden all communication with John Bailey, and had refused to acknowledge any engagement between the two. Gertrude spent much of her time wandering through the grounds, or taking long cross-country walks. Halsey played golf at the Country Club day after day, and after Louise left, as she did the following week, Mr. Jamieson and I were much together. He played a fair game of cribbage, but he cheated at solitaire. The night the detective arrived, Saturday, I had a talk with him. I told him of the experience Louise Armstrong had had the night before, on the circular staircase, and about the man who had so frightened Rosie on the drive. I saw that he thought the information was important, and to my suggestion that we put an additional lock on the east wing door he opposed a strong negative. “I think it probable,” he said, “that our visitor will be back again, and the thing to do is to leave things exactly as they are, to avoid rousing suspicion. Then I can watch for at least a part of each night and probably Mr. Innes will help us out. I would say as little to Thomas as possible. The old man knows more than he is willing to admit.” I suggested that Alex, the gardener, would probably be willing to help, and Mr. Jamieson undertook to make the arrangement. For one night, however, Mr. Jamieson preferred to watch alone. Apparently nothing occurred. The detective sat in absolute darkness on the lower step of the stairs, dozing, he said afterwards, now and then. Nothing could pass him in either direction, and the door in the morning remained as securely fastened as it had been the night before. And yet one of the most inexplicable occurrences of the whole affair took place that very night.