He came back at five thousand feet, slowly--until the ship lurched, and he saw the right wing tip vanish in a shower of molten metal. He threw the ship over and away from the invisible beam; the plane writhed and twisted across the last half mile of sky. He was over them when he pulled into a tight spiral, then he swung the pistol grip that controlled the gun until the dot in the crystal was merged with the target of clustering red forms. The gun sputtered. Below the plane, the quiet desert heaved its smooth surface convulsively into the air. Even above the roar of the motor Smithy heard the terrific thunder of that one long explosion. Above the rim of the forward cockpit Culver's head rolled uneasily; his voice, thick and uncertain, came back through the phone; and later--only a matter of minutes later, though fifty miles away--Smithy set the plane down on a level expanse of sand and tore frantically at his belt. Colonel Culver was weakly raising his head. * * * * * "What hit us?" he demanded when Smithy got to him. "Did I crash?" He looked about him with dazed eyes from which he never would have seen again, but for the protection of his goggles. "Fire," said Smithy tersely. "They did it, the devils, and it wasn't a flame-thrower, either. There wasn't a flash of their cursed green light. It just flicked us for a second. You got the worst of it. Your half roll saved us. That thing, whatever it was, would have ripped our left wing off in a second." He was looking at the forward cockpit where the metal fuselage was melted. The leather cushioning around the edge was black and charred. Culver's helmet had protected him, but half of his face was seared as if it had been struck by a white flame. "But we got some of them: they know we can hit back...." Smithy began, but knew he was speaking to deaf ears. Again his passenger had lapsed into unconsciousness. Quickly he disconnected their own radio receiver and threw on the emergency radio siren. Ahead of them for a hundred miles an invisible beam was carrying the discordant blast. Then, with throttle open full, regardless of levels and of air traffic that tore frenziedly from his path, he drove straight for the home field. * * * * * In the office of the Governor, the radio newscaster was announcing last-minute items of interest. The Governor switched off the instrument as Smithy entered, supporting the tall figure of Colonel Culver, whose face and head were swathed in bandages. Culver had insisted upon accompanying him for the rendering of their report, though Smithy had to do the talking for both of them. He outlined their experience in brief sentences. "And now," he was saying grimly, "you can go as far as you please, Governor. You've got a man's sized fight on your hands. We don't know how many there are of them. We don't know how fast they'll spread out, but--"