Not a sound disturbed the silence of the deserted place, save when the slight breeze sighed through the trees of the adjoining coppice, and swayed some invisible shutter which creaked upon its rusty hinges. An owl hooted, and the detective was on the alert in a moment. It was a well-known signal. Was the owl a feathered one or a human mimic? No other sound followed, until the breeze came again, whispered in the coppice, and shook the shutter. Then the chauffeur's whistle came, faintly, and with something tremulous in its note; for the adventure, though it offered little novelty to the experience of the Scotland Yard man, was dangerously unique from the mechanic's point of view. But where the Right Hon. Walter Belford led it was impolitic, if not impossible, to decline to follow. Yet, the whistle spoke of a man not over-confident. "Severac Bablon" was a disturbing name! Sheffield pressed the knob of the torch and stepped into the bare and dirty room beyond. The beam of the torch swept the four walls, with faded paper peeling in strips from the damp plaster; showed a grate full of rubbish, a battered pail, and a bare floor littered with debris of all sorts, great cavities gaping between many of the planks. A cupboard was searched, and proved to contain a number of empty cans and bottles--nothing else. Into the next room went the investigator, to meet with no better fortune. The third was a big kitchen, empty; the fourth a paved scullery, also empty--with the chauffeur at the door, holding his spanner in readiness for sudden assault. "Upstairs!" said Sheffield shortly. Up the creaking stairs they passed, their footsteps filling the place with ghostly echoes. A square landing offered four doors, all closed, to their consideration. Sheffield paused, and listened. The owl had hooted again. He directed the ray of the torch upon the door on the immediate right of the stairhead. "We're short-handed for this!" he muttered; "but it has to be risked now. Stay where you are and be on the alert. Watch those other doors." He tried the handle. The door was locked. To the next one he passed without hesitation. It yielded to his hand, and he flashed the light about a bare room, with half of the ceiling sloping down to the window. In the corner beyond this window a second door was partly concealed by the recess. The inspector stepped across the floor and threw the door open. Then events moved rapidly. Someone literally shot into the room behind him, falling with a crash that shook the place like thunder. _Bang!_ sounded through the house, and a key turned in a lock! Sheffield spun round like an unwieldy top, and saw the chauffeur struggling to his feet and rubbing his head vigorously. The detective made no outcry, nor did he waste energy by trying a door he knew to be locked. He stood, keenly alert, and listened. Footsteps rapidly receded down the stairs. "Who did it? How did he get behind me?" muttered the dazed chauffeur.