"The door gave at last, and I stumbled into the large room beyond--all dim from the branches of the great trees outside the windows. For a moment I could do nothing but flinch at the faint evil odor that immediately struck my nostrils. Then, turning on the electric light and glancing around, I glimpsed a nameless blasphemy on the yellow and blue rug. "It lay face down in a great pool of dark, thickened blood, and had the gory print of a shod human foot in the middle of its naked back. Blood was spattered everywhere--on the walls, furniture and floor. My knees gave way as I took in the sight, so that I had to stumble to a chair and slump down. The thing had obviously been a human being, though its identity was not easy to establish at first, since it was without clothes and had most of its hair hacked and torn from the scalp in a very crude way. It was of a deep ivory color, and I knew that it must have been Marceline. The shoeprint on the back made the thing seem all the more hellish. I could not even picture the strange, loathsome tragedy which must have taken place while I slept in the room below. When I raised my hand to wipe my dripping forehead I saw that my fingers were sticky with blood. I shuddered, then realized that it must have come from the knob of the door which the unknown murderer had forced shut behind him as he left. He had taken his weapon with him, it seemed, for no instrument of death was visible here. "As I studied the floor I saw that a line of sticky footprints like the one on the body led away from the horror to the door. There was another blood-trail, too, and of a less easily explainable kind; a broadish, continuous line, as if marking the path of some huge snake. At first I concluded it must be due to something the murderer had dragged after him. Then, noting the way some of the footprints seemed to be superimposed on it, I was forced to believe that it had been there when the murderer left. But what crawling entity could have been in that room with the victim and her assassin, leaving before the killer when the deed was done? As I asked myself this question, I thought I heard fresh bursts of that faint, distant wailing. "Finally, rousing myself from a lethargy of horror, I got on my feet again and began following the footprints. Who the murderer was, I could not even faintly guess, nor could I try to explain the absence of the servants. I vaguely felt that I ought to go up to Marsh's attic quarters, but before I had fully formulated the idea I saw that the bloody trail was indeed taking me there. Was he himself the murderer? Had he gone mad under the strain of the morbid situation and suddenly run amok?