There came a sudden blare of music from the great ballroom below, and the woman who stood alone at an open window on the first floor shrugged her shoulders and shivered a little. The night air blew in brisk and cold upon her uncovered neck, but except for that slight, involuntary shiver she scarcely seemed aware of it. The room behind her was brilliantly lighted but empty. Some tables had been set for cards, but the cards were untouched. Either the attractions of the ballroom had remained omnipotent, or no one had penetrated to this refuge of the bored--no one save this tall and stately woman robed in shimmering, iridescent green, who stood with her face to the night, breathing the chill air as one who had been on the verge of suffocation. It was evidently she who had flung up the window. Her gloved hands leaned upon the woodwork on each side of it. There was a certain constraint in her whole attitude, a tension that was subtly evident in every graceful line. Her head was slightly bent as though she intently watched or listened for something. Yet nothing could have been audible where she stood above the hubbub of music, laughter, and stamping feet that rose from below. It filled the night with uproar. Nor was there anything but emptiness in the narrow side-street into which she looked. The door of the room was ajar and gradually swinging wider in the draught. Very soon it would be wide enough for anyone passing in the passage outside to spy the slim figure that stood so motionless before the open window. It was almost wide enough now. Surely it was wide enough, for suddenly it ceased to move. The draught continued to eddy round the room, stirring the soft brown hair about the woman's temples, but the door stood still as at the behest of an unseen hand. For fully half a minute nothing happened; then as suddenly and silently as a picture flashed from a magic lantern slide, a man's head came into view. A man's eyes, dusky, fierce, with something of a stare in them, looked the motionless figure keenly up and down. There followed another interval as though the intruder were debating with himself upon some plan of action, then, boldly but quite quietly, he pushed the door back and entered. He was a slight, trim man, clean-shaven, with high cheek-bones that made a long jaw seem the leaner by contrast. His sleek black hair was parted in the middle above his swarthy face, giving an unmistakably foreign touch to his appearance. His tread was light and wary as a cat's. His eyes swept the room comprehensively as he advanced, coming back to the woman at the window as though magnetically drawn to her. But she remained quite unaware of him, and he, no whit disconcerted, calmly seated himself at one of the tables behind her and took up a pack of cards. The dance-music in the room below was uproariously gay. Some of the dancers were singing. Now and then a man's voice bellowed through the clamour like the blare of a bull.