"The dirty, murdering rats!" Brian's voice ripped out in a fury of outrage. "They didn't have a chance!" "Don't get excited," Crystal told him in a dead, flat voice. "That's just normal practice. If you'd stuck your nose out of your laboratory once in a while, you'd have heard of these things." "But why--" He ducked away instinctively as a flight of bullets spanged through the fuselage. "They're after us now!" Crystal's answer was to yank the ship into a rocketing climb. The police were watching for that. The big ship roared up after them. "Just follow along, suckers," Crystal invited grimly. She snapped the ship into a whip stall. For one nauseating moment they hung on nothing, then the ship fell over on its back and they screamed down in a terminal velocity dive, heading for the safety of the lower valley mists. The heavier police ship, with its higher wing-loading, could not match the maneuver. The rebel craft plunged down through the blinding fog. Half-seen, ghostly fingers of stone clutched up at them, talons of gray rock missed and fell away again as Crystal nursed the ship out of its dive. "_Phew!_" Brian gasped. "Well, we got away that time. How in thunder can you do it?" "Well, you don't do it on faith. Take a look at that fuel gauge! We may get as far as our headquarters--or we may not." * * * * * For twenty long minutes they groped blindly through the fog, flying solely by instruments and dead reckoning. The needle of the fuel gauge flickered closer and closer to the danger point. They tore loose from the clinging fog as it swung firmly to "Empty." The drive sputtered and coughed and died. "That's figuring it nice and close," Crystal said in satisfaction. "We can glide in from here." "Into where?" Brian demanded. All he could see immediately ahead was the huge bulk of a mountain which blocked the entire width of the valley and soared sheer up to the high-cloud level. His eyes followed it up and up-- "Look! Police ships. They've seen us!" "Maybe they haven't. Anyway, there's only one place we can land." The ship lunged straight for the mountain wall! "Are you crazy? Watch out--we'll crash!" "You leave the flying to me," Crystal snapped. She held the ship in its glide, aiming directly for the tangled foliage of the mountain face. Brian yelped and cowered instinctively back. The lush green of the mountainside swirled up to meet them. They ripped through the foliage--there was no crash. They burst through into a huge, brilliantly lighted cavern and settled to a perfect landing. Men came running. Crystal tumbled out of her ship. "Douse those lights," she shouted. "The police are outside." A tall, lean man with bulbous eyes and a face like a startled horse, rushed up to Crystal. "What do you mean by leading them here?" he yelled, waving his hands. "They jumped us when we had no fuel, and quit acting like an idiot."