"Appointment?" he repeated with the rising inflection, taking the paper. "It was delivered at my hotel half an hour ago," she told him. "I presumed you ..." "No," said Staff. "Half a minute...." He shut the door and unfolded the note. The paper and the chirography, he noticed, were identical with those of the note received by Iff from Hartford. With this settled to his satisfaction, he read the contents aloud, raising his voice a trifle for the benefit of the listener in the back room. "'If Miss Landis wishes to arrange for the return of the Cadogan collar, will she be kind enough to call at Mr. Staff's rooms in Thirtieth Street at a quarter to ten tonight. "'N. B.--Any attempt to bring the police or private detectives or other outsiders into the negotiations will be instantly known to the writer and--there won't be any party.'" "Unsigned," said Staff reflectively. "Well?" demanded Alison, seating herself. "Curious," remarked Staff, still thinking. "Well?" she iterated less patiently. "Is it a practical joke?" "No," he said, smiling; "to me it looks like business." "You mean that the thief intends to come here--to bargain with me?" "I should fancy so, from what he says.... And," Staff added, crossing to his desk, "forewarned is forearmed." He bent over and pulled out the drawer containing his revolver. At the same moment he heard Alison catch her breath sharply, and a man's voice replied to his platitude. "Not always," it said crisply. "Be good enough to leave that gun lay--just hold up your hands, where I can see them, and come away from that desk." Staff laughed shortly and swung smartly round, exposing empty hands. In the brief instant in which his back had been turned a man had let himself into the study from the hall. He stood now with his back to the door, covering Staff with an automatic pistol. "Come away," he said in a peremptory tone, emphasising his meaning with a flourish of the weapon. "Over here--by Miss Landis, if you please." Quietly Staff obeyed. He had knocked about the world long enough to recognise the tone of a man talking business with a gun. He placed himself beside Alison's chair and waited, wondering. Indeed, he was very much perplexed and disturbed. For the first time since Iff had won his confidence against his better judgment, his faith in the little man was being shaken. This high-handed intruder was so close a counterpart of Mr. Iff that one had to look twice to distinguish the difference, and then found the points of variance negligible--so much so that the fellow might well be Iff in different clothing and another manner. And Iff could easily have slipped out of the bedroom by _its_ hall door. Only, to shift his clothes so quickly he would have to be a lightning-change artist of exceptional ability. On the whole, Staff decided, this couldn't be Iff. And yet ... and yet ...