Above him was a pale circle of light. Tipping the edge of a vast crater mouth high above was a rim of brilliance. Earthlight! Chet was suddenly certain that he was seeing that glow for the last time as the circle went black, and there came to him the unmistakable clang of metal where a door was shut. Through the countless mingled emotions that filled him he was wondering what manner of creatures these were into whose hands he had fallen. Intelligent, beyond a doubt, in their own way; he could not question the evidence of his own eyes and ears. They were able to work in metals and to seal the mouth of this lunar tomb. But he was still alive; he could not give up now. This adventure upon which he had launched with such high hopes had turned out differently than expected; but, he told himself, it was not ended yet. And, instead of a lifeless globe, he had found this: a place peopled with strange, half-human life. And, more marvelous still, instead of Haldgren, whom he had come to seek, there had been a girl! * * * * * Chet had recovered his ability to breathe, had made sure that the oxygen tank was intact; and now he called softly into the blackness of this dark vault where he had seen her thrown. "Are you alive?" he asked. "Can you hear me?" For answer came quick rustling of moving bodies, the smooth rasping of wings on leathery wings, hands that fumbled for him, then closed about arms and legs and throat, while in his ears was a chattering of high-pitched squeals. Again he was lifted in air, held there in the grip of a score of lean, long-fingered hands. He was nerving himself to undergo without flinching whatever new torture might be in store. Yet he thrilled inexplicably as through the sounds of these things about him, he heard a muffled: "Yes--yes! Oh, I am glad--" The sentence was unfinished. Before Chet's eyes a light was growing. A mere slit at first, it grew to a luminous circle in the rocky floor. And as it opened, he felt the pressure of his metal suit upon his body, where before it had been slightly ballooned by the pressure of oxygen he had maintained. With the opening of this door to another subterranean chamber had come a renewed atmospheric pressure. And now, in the denser gas, he saw, in ghastly silhouette against the lighted pit, flying figures that floated and soared on outstretched wings of inky black. * * * * * Beside him and above he heard the swishing flutter of other wings; he felt himself lifted from the floor; he was being floated out above the luminous pit by the flying things that held him. No direct glare came from below, but a soft violet radiance. It shone full upon him--past him--to light up and give detail to those faces that had been featureless before. Chet had just one moment of fascinated staring into the diabolical, pasty faces where narrow, red eyes stared back into his. Then the squealing voices were stilled!