The four couples placed bets. Madame Sin watched out of dark, exotic eyes. She turned slowly, with her gold-link purse casually held in her left hand; turned so that she made a complete, leisurely circle, as though searching for someone. Then, with her red lips still shaped in a smile, she faced the table again. The croupier spun the wheel, snapped the ball into it. The eight players leaned to watch it.... And in that position they remained. There was no movement of any sort from any one of them. It was as though they had been frozen to blocks of ice by a sudden blast of the cold of outer space; or as though a motion picture had been stopped on its reel so that abruptly it became a still-life, with all the actors in mid-move and with half-formed expressions on their faces. A tall blond girl was bent far over the table, with her left hand hovering over her bet, on number twenty-nine. Beside her a man had a cigarette in his lips and a lighter in his left hand which he had been about to flick. Two other men were half facing each other with the lips of one parted for a remark he had begun to make. The rest of the eight were gazing at the wheel with arms hanging beside them. And exactly in these positions they remained, for minute after minute. During that time Madame Sin looked at them; and her smile now was a thing to chill the blood. You couldn't have told why. Her face was as serene-looking as ever, and there were no tangible lines of cruelty in evidence in her face. Yet she looked like a she-fiend as she stared around. She walked to the croupier, who stood gazing at his wheel, with his mouth open in the beginning of a yawn. Down the hall came the clang of elevator doors, and the sound of laughter and voices. Madame Sin glided toward the door. There she paused, then went purposefully back to the table. She went swiftly from one to another of the frozen, stark figures in their life-like but utterly rigid positions, then back to the door. Smiling, she left the room, passing five or six people who were about to enter it for a little gambling. She was almost to the elevator shafts when she heard a woman's scream knife the air, followed by a man's hoarse shout that expressed almost as much horror as the scream had done. Still smiling, utterly composed, she stepped into an elevator--and the elevator boy shivered a bit as he stared at her. He had not heard the scream, did not know that anything was wrong. He only knew that something in this lovely woman's smile sent cold fingers up and down his spine. * * * * * It was a grim, white-faced trio that sat in the conference room of the Blue Bay Hotel at eleven next morning. Chichester nor Gest nor Kroner--none had had a moment's sleep all night. They had been in Doctor Grays' suite with Weems when a shivering man--a well-known young clubman, too, which was unfortunate--stumbled up to tell of the dreadful thing to be seen in the roulette room.