He lifted the weapon, pointed it toward where the Aliens should be, and depressed the little trigger, moving the rheostat back and forth to be sure he had the lethal frequency well covered. He felt a tremor on the floor beside him, and his eyes caught a glimpse of Pat at his side before he could force his gaze toward space again. She was shouting something inside her helmet. Then he caught the first visible sign of the Alien ship, already within miles of the building, and big enough to show in the side-light of the sun. It came rushing down in an unchecked plunge, apparently heading straight for him! He strained his eyes, tracing its path. Then he relaxed. It was moving sideways and would land a mile away. _The weapon had worked._ No ship would have risked such speed so near the surface if the pilot had been alive. He gripped Pat by the shoulder, and dragged her to the floor, away from the threat of falling debris. There was no sound, but a tremendous jolt rocked the floor of the building, and for a terror-fraught moment the ground seemed to dance madly. A shaft of greenish-yellow radiance merged with a glaring red that lit up the sky for miles. The ship had struck at a terrific speed--fast enough to reduce everything inside it to a pulp. The instant everything was quiet, Norden sprang to his feet. _Now! There is no time to be lost!_ He caught the thought in time. He couldn't let himself explode in the workroom. He had to get outside, away from the two humans. The compulsion squeezed and writhed in his mind, and he could not throw it off. It was tenfold as strong as the previous commands--and the need to overcome it a hundred times as great. He stumbled toward the seal as Pat stood by. His body slipped through the seal, and he almost bumped into Miles, who was apparently waiting for him. Norden had no spare effort for speech or thought. He headed dumbly for the airlock, determined to get outside as quickly as possible. "Norden!" The general had grabbed his arm, and was following him. "Norden, if you go out there, I'm going with you. Whatever happens will happen to me, too. _You've got to listen!_" He tried to force his way ahead, shaking his arm to free it. The other arm was also carrying a dead weight, and he could see Pat's face close to his own. She was screaming at him. "Bill! Bill, you must listen! We knew it all along! We _knew_ you were a robot! It doesn't matter. If you explode, you'll take us with you!" He hit the lock in savage desperation and the words froze meaninglessly in his ears as he held back the driving urge until he could escape from them. Miles clung grimly. "It's the Aliens, Bill! They want you to explode. The damned Aliens who want to kill you! Do you love them so much you'll kill us all? Or do you hate them?"