Sherikov's guards streamed out onto the plain. Crouching and running, they advanced toward the stalled cars. The police airships screeched down at them, guns thundering. Dixon held his breath. When the missiles arrived-- The first missile struck. A section of the mountain vanished, turned to smoke and foaming gasses. The wave of heat slapped Dixon across the face, spinning him around. Quickly he re-entered his ship and took off, shooting rapidly away from the scene. He glanced back. A second and third missile had arrived. Great gaping pits yawned among the mountains, vast sections missing like broken teeth. Now the missiles could penetrate to the underground laboratories below. On the ground, the surface cars halted beyond the danger area, waiting for the missile attack to finish. When the eighth missile had struck, the cars again moved forward. No more missiles fell. Dixon swung his ship around, heading back toward the scene. The laboratory was exposed. The top sections of it had been ripped open. The laboratory lay like a tin can, torn apart by mighty explosions, its first floors visible from the air. Men and cars were pouring down into it, fighting with the guards swarming to the surface. * * * * * Dixon watched intently. Sherikov's men were bringing up heavy guns, big robot artillery. But the police ships were diving again. Sherikov's defensive patrols had been cleaned from the sky. The police ships whined down, arcing over the exposed laboratory. Small bombs fell, whistling down, pin-pointing the artillery rising to the surface on the remaining lift stages. Abruptly Dixon's vidscreen clicked. Dixon turned toward it. Reinhart's features formed. "Call off the attack." His uniform was torn. A deep bloody gash crossed his cheek. He grinned sourly at Dixon, pushing his tangled hair back out of his face. "Quite a fight." "Sherikov--" "He's called off his guards. We've agreed to a truce. It's all over. No more needed." Reinhart gasped for breath, wiping grime and sweat from his neck. "Land your ship and come down here at once." "The variable man?" "That comes next," Reinhart said grimly. He adjusted his gun tube. "I want you down here, for that part. I want you to be in on the kill." Reinhart turned away from the vidscreen. In the corner of the room Sherikov stood silently, saying nothing. "Well?" Reinhart barked. "Where is he? Where will I find him?" Sherikov licked his lips nervously, glancing up at Reinhart. "Commissioner, are you sure--" "The attack has been called off. Your labs are safe. So is your life. Now it's your turn to come through." Reinhart gripped his gun, moving toward Sherikov. "_Where is he?_" For a moment Sherikov hesitated. Then slowly his huge body sagged, defeated. He shook his head wearily. "All right. I'll show you where he is." His voice was hardly audible, a dry whisper. "Down this way. Come on."