O’Mally sprawled back in his chair with his chest thrown out: "Well, I don’t like to commit myself so early in the game, but there are a few things that seem pretty clear. Though the Azalea Woods Estates were dark when Harland came down somebody was there." "Who?" asked Jack. O’Mally looked sort of pitying at him: "His murderer. This man didn’t attempt the job alone. Must have held Harland in talk in the private office till later when Tony Ford came in and helped, if he didn’t do the actual killing. When _that_ was over Ford went, leaving the other man to carry out the sensational denouement." "What could have been Ford’s motive?" said Mr. George. "Did he know Harland?" O’Mally grinned. "Oh, we’ll find a motive all right. Wait till we’ve turned up the earth in his tracks. Wait a few days." "This ’other man,’ O’Mally," said Mr. Whitney, "have you any ideas about him?" "There you got me stumped," said the detective. "Of course we don’t know Harland’s inner life—had he an enemy and if so who? But—" he paused and let his glance move over the faces of the two young men. "_If_ the thing hadn’t been physically impossible I’d have turned my searchlight eye on Johnston Barker." "Barker!" exclaimed Mr. George. "But Barker was——" O’Mally interrupted him with a wave of his hand— "I _said_ it was physically impossible." The old man got up, shaking himself like a big, drowsy animal and came forward into the lamplight. "Nevertheless, gentlemen," he said quietly, "I’m convinced that it _was_ Johnston Barker." They all gaped at him. I think for the first moment they thought he had some information they hadn’t heard and waited open-mouthed for him to give it to them. But he stood there, smiling a little, his eyes moving from one to the other, sort of quizzical as if their surprise tickled him. "Now, father," said Mr. George, "what’s the sense of saying that when we know that Barker was on the floor above, unable to get out without being seen?" "I know, George, I know," said his father mildly. "I’m perfectly willing to admit it. But in that room—on the floor above—there had been a quarrel between the two men. Since the disappearance of Barker there’s been a good deal of speculation as to the nature of that quarrel. That is, the public has speculated; _I_ have felt sure. After the disappearance that quarrel, as far as I could see, had only one interpretation—the lawyer had discovered the perfidy of his associate and threatened exposure. And we all know that the only silent man is a dead man." "That’s all very well," said O’Mally, "but it doesn’t get round the fact that Barker couldn’t possibly have been there to instigate a murder, or help in murder or commit a murder himself."