The exclamation was called from him by a sudden movement on the part of the captor. The third man must have made a noise, for the captor turned sharply. At the instant he did so the rustler's pistol flashed in the sunlight. The watchers on the plateau did not hear the report at once, and when they did it came to them only faintly--a slight sound which was barely distinguishable. But they saw a sudden spurt of flame and smoke. The captor reeled drunkenly in his saddle, caught blindly at the pommel, and then slid slowly down into the grass of the plains. Ferguson drew a deep breath and, turning, looked sharply at Miss Radford. She had covered her face with her hands and was swaying dizzily. He was up from the rock in a flash and was supporting her, leading her away from the edge of the plateau. She went unresisting, her slender figure shuddering spasmodically, her hands still covering her face. "Oh!" she exclaimed, as the horror of the scene rose in her mind. "The brutes! The brutes!" Feeling that if he kept quiet she would recover from the shock of the incident sooner, Ferguson said nothing in reply to her outbreaks as he led her toward the ponies. For a moment after reaching them she leaned against her animal's shoulder, her face concealed from Ferguson by the pony's mane. Then he was at her side, speaking firmly. "You must get away from here," he said, "I ought to have got you away before--before that happened." She looked up, showing him a pair of wide, dry eyes, in which there was still a trace of horror. An expression of grave self-accusation shone in his. "You were not to blame," she said dully. "You may have anticipated a meeting of those men, but you could not have foreseen the end. Oh!" She shuddered again. "To think of seeing a man deliberately murdered!" "That's just what it was," he returned quietly; "just plain murder. They had him between them. He didn't have a chance. He was bound to get it from one or the other. Looks like they trapped him; run him down there on purpose." He held her stirrup. "I reckon you've seen enough, ma'am," he added. "You'd better hop right on your horse an' get back to Bear Flat." She shivered and raised her head, looking at him--a flash of fear in her eyes. "You are going down there!" she cried, her eyes dilating. He laughed grimly. "I cert'nly am, ma'am," he returned. "You'd better go right off. I'm ridin' down there to see how bad that man is hit." She started toward him, protesting. "Why, they will kill you, too!" she declared. He laughed again, with a sudden grim humor. "There ain't any danger," he returned. "They've sloped." Involuntarily she looked down. Far out on the plains, through the break in the ridge of hills, she could see two horsemen racing away. "The cowards!" she cried, her voice shaking with anger. "To shoot a man in cold blood and then run!" She looked at Ferguson, her figure stiffening with decision.