It took but a short time to make their final preparations. Larry taught a half dozen Underlings how to operate his howler, also taught them how to build others like it. "Now get to work," he told them grimly. "Make as many of these gadgets as you can. And make 'em light and small, portable, so you can carry them around with you." He turned to Sert. "Well, this is it, pal. Keep your eye peeled for the signal. 'One if by land and two if by sea.'" Sert said puzzledly, "What's that?" "Skip it. What I mean is, watch the dome. If you smell something funny, that'll be fresh air, and it'll mean Sandy and I have taken the fort. Attack then. We'll be in a position to crack a whip over the runts." He held out his hand. "Be seein' you, guy! Let's go, Sandy." Together they made their way through the labyrinth of chambers to their own cell. This time Larry fumbled less with the mitogenic locks that barred their progress; it took them but a few minutes to make the journey. Yet even at that they barely returned in time. As they came through the chambers, Larry reminded Sandra, "We're banking on the fact that Harg doesn't know we've been out of our coop. That's our story and we're stuck with it. If by any chance he or a guard happened in while we were out, we're sunk, but--" "It's a chance worth taking," nodded the girl. "Yes. The big idea is to get to that control chamber. I think we can do it because Harg, big-shot as he may be, has one bad failing. Human vanity. So remember, play up to whatever I say." "Okay, boss!" said Sandra meekly. But there was a crinkle of laughter in her eyes. Then they were back in their own cell, the door behind them was sliding closed--and almost immediately the one before them was sliding open to admit Harg-Ofortu and a brace of armed guards! There was fretfulness on the little scientist's face, fretfulness that turned to swift suspicion as Larry and Sandra started guiltily. His eyes swept the room, returned to Larry. Larry felt the raw demand of Harg's first directed thought, "Can these two--?" then he felt the tenuous fingers of Harg's probing mentality seeking information from his mind. With an effort he forced himself to think of simple, unimportant things. He concentrated on the tag end of an old nonsense rhyme-- /P "Oh, do I is? And am I be? Or couldn't I have used to be? Oh, cruel fate, which was to me; I used to ain't!" P/ --and chuckled inwardly to catch the shocked repercussion of Harg's amazed, "Incredible! These barbarians are simple minded children!" Then Harg spoke. Or directed a thought to the Twentieth Century couple, his equivalent of speech. "You will come with me!" Larry pretended alarm. "Why? We are comfortable here. We don't want to--" "I am doing," Harg advised him crisply, "that which is best for you. There has been a little--er--disturbance in the city. I am removing you to safer quarters. I will not have my experiments upset by--" "By--?" prodded Larry.