"Well, after that, he locks himself up in his workroom, so Mrs. Perrin says, she being housekeeper, as you know, sir, leaving word not to disturb him for dinner. "We don't think so much of that, Mr. Butler being took with streaks of working at all hours, as you know. But when Miss Hope came home unexpected this morning--" "What?" "She cut her visit a few days short, her aunt having other house guests turn up unexpected like, and Miss Hope arrives first thing this morning, being here when I return from town after mailing the letter to you, sir. "Mrs. Perrin had just told her about the master, and Miss Hope looks into his room. He isn't there, and the bed hasn't been slept in. 'The poor dear,' she says, 'he's worked himself half to death, and dropped off on that horrible cot he keeps in his laboratory,' says Miss Hope. 'I'll let him sleep.' "But just a few minutes ago, just before you arrived, sir, she became nervous like, and rapped on the door. There wasn't a sound. So she went up to the master's room and found a key, and went in. And now _she_ don't answer, and we were just about ready to call the police!" "Let's go inside!" I hurried by Perrin and through the cool, quiet hall to the broad door that opened into the big room at the back of the house, which was Vic's laboratory. * * * * * "Vic! Hope!" I pounded as hard as I could, shouting their names. There was no response. "Is there another key, Perrin?" I snapped. "No, sir; none that I know of. The master was mighty fussy about his workroom." "Can we get in through the windows?" "No. They're barred, if you remember rightly, and fitted with this frosted glass, so you can't see in, even." "Then get me an ax!" I commanded. "Quick!" "An ax?" hesitated Perrin. "An ax--and be quick about it!" Perrin mumbled a protest and hurried away. I turned to Mrs. Perrin, who had come up to determine the result of my shouting. "How long is it since Miss Hope went in there?" "How long, sir? I'd say about twenty minutes before you came. Maybe twenty-five. I wasn't paying any particular attention, sir. She just got the key and went in. After a few minutes I heard something buzzing in there, and I thought maybe Mr. Butler was showing her some new gadget of his, like he was always doing. Then there was a telephone call for him, and I couldn't make neither of them answer; that's when Mr. Perrin and I began to get worried." "I see." Perrin came hurrying up with the ax, and I motioned them aside. I swung the ax, and the head of the weapon crashed against the lock. The knob dropped to the floor with a clatter, but the door gave not at all. I brought the ax down again, and something cracked sharply. The third blow sent the door swinging wide. Cautiously, fearing I know not what, I entered the familiar room. Nothing, apparently, had been disturbed. There was no sign of disorder anywhere. The blankets on the narrow cot in the corner of the room had not been unfolded.