The Titanians behind Bud and Rocky prodded. Helpless in the face of vastly superior odds, the two S.I.D. men stumbled forward off the highway and across the rough desert, toward the hill dully gleaming a short distance away. * * * * * Seated at the controls of the tiny roller, Lynn Graham was thinking furiously as she drove. Obviously there was no chance of escaping so long as that flabby-fleshed parody of manhood crouched behind her with a Haemholtz leveled on the small of her back. Yet somehow she must get away ... get to the Fort and bring the Patrol.... Guile, that was her only chance. Take advantage of the slow-thinking Titanian's inferior mentality. She turned and smiled back over her shoulder. "Have you ever been to the Patrol Base before?" she asked pleasantly. Grushl answered mechanically, "Yes. Many times--" Then the implication of her words penetrated his brute brain. "Before? But we are not going to the Patrol Base." "Maybe," retorted Lynn airily, "_you're_ not, but _I_ am. Just as fast as this roller will carry me." Grushl's heavy brows gathered in perplexity. "But, no! You are to drive to the office building, there await the Master." Lynn laughed. "What nonsense! So long as I am the driver of this roller, I will take it where I wish." "Then," said Grushl thoughtfully, "I will be forced to shoot you. You must not escape." "But you can't do that," Lynn pointed out shrewdly. "Factor Grossman said nothing about shooting me. He ordered that I was to be kept safely until he came." "Yes," pondered the Titanian, "that is true. But I see no other way to--" "I am afraid you will have to let me drive to Fort Beausejour. So long as I am driving, there is nothing you can do to prevent me taking the roller where I wish." Grushl, who had been wrestling laboriously with the problem, now suddenly saw the light. His deepset eyes brightened. "Oh, no! There is another way!" he cried triumphantly. "_I_ will drive the roller!" "B-but--" cried Lynn. "That is the solution. Stop the roller. You and I will change places. I will drive; you will move back here." Obediently, Lynn drew the car to a halt, slipped from the driver's cubicle as the Titanian moved from the rear seat to take her place. Grushl smiled at her complacently. "You see?" he boasted. "It is really very simple. Now I can stop the roller wherever I wish. The Master will be obeyed." He reached for the controls laying his Haemholtz on the cushion beside him as he did so. That was what Lynn had been waiting for. In one sudden motion she leaned forward, scooped up the weapon. "Sorry, Grushl!" she cried. "But it's you or me--" She slashed the tube down hard upon the Titanian's scalp. Grushl groaned once, heavily--and sagged. His hands, falling away, dragged at the steering control-stick. In an instant the car jerked into convulsive motion, charged toward the edge of the road.