I saw what was like a small closet, about two feet deep and perhaps three feet wide. At the back of it, that is, against the walls of the adjoining room in the other house, we could see the shape of a similar door, and the secret was out. There was no need to open that other door to know that it led to Ruth Schuyler's rooms. There was yet more telltale evidence. In the little cupboard between the houses was a small safe. This Stone had opened and in it was the black wig of Vicky Van and also a brown wig which I recognized at once as Julie's well-remembered plainly parted front hair. "You see, Tibbetts is Julie," said Fibsy, in such a heart-broken and despairing voice that I felt the tears rush to my own eyes. Vicky's wig! The loops of sleek black hair, the soft loose knot behind, the delicate part, all just as it crowned her little head--Ruth's head! Oh, I couldn't stand it! It was too fearful! "This other door," Stone said, "opens into Mrs. Schuyler's bathroom. That I know. You see, she had to have this entrance from some room absolutely her own. Her bathroom was safe from interruption, and when she chose she slipped through from one house to the other and back at will." "No, I can't understand it," I insisted, shaking my head. "If she came in here as Ruth Schuyler why wasn't she seen?" "Because, before she was seen, she had made herself over into Victoria Van Allen. She had donned wig and make-up, safe from interruption, here in her boudoir. This make-up she removed before returning to the Schuyler house in her role of Mrs. Schuyler." "It is too unbelievable!" "No; it is diabolically clever, but quite understandable. Julie and Tibbetts are the same. This confidential woman looked after her mistress' safety on both sides. She remained when Vicky Van disappeared. She looked after everything, took care of details, attended to tradesmen and all such matters, and when ready followed Mrs. Schuyler into the other house, or went from here to her rooms a few blocks away and later came from them. When there were to be parties, Julie left the Schuyler house early, came here and made preparations, and then as late as ten or eleven o'clock maybe, Mrs. Schuyler came in from her home, when her own household thought her abed and asleep. She could go back in the early morning hours, with no one the wiser. Or, if she chose and she did when her husband was out of town, she could pretend she had gone away for a visit and stay here for days at a time." I began to see. Truly the wall's tongue had spoken. If this awful theory of Stone's were true, it could only be managed in this way. I remembered how long and how often Vicky Van was absent from her home. I remembered that sometimes she was late in arriving at her own parties, although she always came down from upstairs in her party regalia. "How did you come to suspect Tibbetts?" I asked, suddenly.