“Miss Neobard has explained to you that this is a confidential interview, I hope. Whatever you say to me will be a secret between ourselves, unless you authorize me to make use of it. It is for you to decide whether your daughter is to remain in the room, of course.” The mother stretched out a hand and took hold of one of her protector’s, who answered for her. “I have promised my mother to remain.” “Very good. I had better begin by reading you this advertisement. It appeared in the paper yesterday.” He read out the invitation from Messrs. James, Halliday and James to the patients of the late Dr. Weathered to apply for the return of their correspondence and continued: “The solicitor who put in this advertisement refused to give the name of the client who is instructing him. Will you tell me if it is you?” Mrs. Neobard shook her head faintly without speaking. “Can you tell me if your late husband left a will, and who is his executor?” “I can answer that question,” Sarah put in. “My mother is sole executor and he has left everything to her. She wanted to renounce execution; but the lawyer told her that it would be no use, as the law would make her administrator. She is not going to take a farthing of his money, if there is any.” “Quite so; then Mrs. Neobard is the only person who is lawfully entitled to deal with any papers Dr. Weathered left behind him. Can you explain to me how these letters came to be in the possession of this solicitor, or the person for whom he is acting?” The flush had faded from the widow’s cheeks, leaving her very pale. “I can’t explain,” she said in a whisper. “Does it matter?” her daughter asked. “As long as these people get their letters back again, what does it matter who they got them from?” “They won’t get them; that is what matters,” the physician said gravely. “There is a criminal behind this advertisement. I must explain to you and to Mrs. Neobard, if she doesn’t know already, what these letters were about.” Very deliberately and keeping his eyes fixed on the agitated woman all the time, Tarleton outlined the story of his discoveries. He was careful not to mention names. He explained why the doctor’s case-book had been taken from the safe, and why that precaution had proved useless. The dead man’s real hold over his victims had been through the letters he had persuaded them to write to him; those letters had been signed with a cipher, and the object of the advertisement was to make the writers disclose their identity so that they might be blackmailed by the holder of their secret confessions. The widow’s distress became pitiable as the explanation proceeded. There could be no doubt that she was no party to the plot and hardly a doubt that its revelation had come to her as a complete shock. As for Sarah Neobard, her fine eyes fairly blazed with indignation.