Wat obeyed reluctantly. He shook his fist high in the air, and started to run again. It was not an instant too soon, either. A beam slithered down the smoldering air, and the Earth literally boiled under its impact, directly on the spot where Wat had stopped to shake his fist. All about them the terrible rays were slashing now. But a last desperate burst of speed carried the Earthmen onto a wide enclosed portico, in the old manner. Hilary pounded on the vita-crystal door. It was tightly locked. * * * * * "Step back a moment," Morgan rumbled. Hilary obeyed. The big man spat thoughtfully upon his hands, worked his shoulders tentatively. Then he too retreated to the outermost edge of the portico. Above, the crystal suddenly shattered. Sharp-edged fragments showered down upon them. There was little time to waste. Grim heaved forward in a slanting rush, right shoulder extended. He crashed into the locked door like a runaway train. There was a grinding noise, a smash of crystal, and his shoulder was through, incased in a halo of bright, sharp edges. The big man staggered back, his shoulder streaming blood from a hundred cuts. His face was pale and drawn. "Good fellow," Wat yelled, "even though you are an overgrown ox." He darted in behind the man-mountain like a twisting snake. His deft fingers reached in through the shattered crystal, pressed something on the inside. The door slid into its wall pocket with a sound of grinding glass. Wat burst into the opened room first, Grim right behind him. Hilary brought up the rear, Grim's great bulk blotting out for the moment any view of the interior. There was a sudden gasp--a girl's voice. "Wh--What does this mean?" She was tremulous, yet unafraid. Hilary stopped suddenly as though brought up against a solid wall. His heart pounded madly. That voice--but it was utterly impossible! Wat answered, gallantly. "Sorry to annoy you, miss, but they're after us. My partner here's wounded." "Oh, you poor man." There was quick sympathy in the clear tones. "But who is after you?" A splintering crash resounded outside. "The Mercutians, as you no doubt hear," the little man responded with faint irony. The girl gasped again. "Oh my God!" There was silence. Hilary strained his ears, yet took care to keep hidden behind Grim's huge frame. What would she do now? It seemed to him as if the whole world depended on her reply. The girl broke the silence. She had come to a swift decision. "They must not get you. Go upstairs, quietly, into the chamber on the left of the hall. It's my bedroom. Their search beams can not penetrate it; the walls are draped with lead-encrusted curtains. I'll stay down here and try to throw them off the trail." Hilary's heart recommenced beating. A gush of joy overwhelmed him. The girl had proven herself. Grim spoke, for the first time. "You know the penalty of course, for hiding us."