"You mean that those—those things—moved and lived in the outside world a hundred thousand years ago?" he asked dazedly. "But there is no indication of there ever having been any such creatures among Earth's early forms of life."
"Fool!" There was angry disdain in Layroh's resonant voice. "They who slumber here are a race born far from this planet. They are the Shining Ones of Rikor. Rikor is a tiny planet circling a wandering sun whose orbit is an ellipse so vast that only once in a hundred thousand years does it approach your solar system. Rikor's sun was nearly dead and the Shining Ones had to find a new home soon or else perish. Then their planet swung near the Earth, and their scouts returned with the news that Earth was ideally suited for their purpose. There were barely five hundred of the Shining Ones all told, and they migrated to Earth in a body."
"And they've been in this cavern ever since, sealed up like tadpoles in fish bowls?" The question came from Garrigan, a strapping sandy-haired Irishman whose first blind panic at the black ray's menace was swiftly giving way to curiosity.
"It was your ancestors who drove the Shining Ones into their retreat here," Layroh answered grimly. "When the Shining Ones arrived upon Earth they found the planet already in the possession of a race of human beings whose science was so far advanced that it compared favorably even with the science of Rikor. This race was comparatively few in numbers, and was concentrated upon a small island-continent known as Atlantis. Shining Ones and Atlanteans met in a war of titans, with a planet as the stake. The Shining Ones were vanquished in that first battle. They lost a fifth of their number and barely half a dozen of their smallest space ships escaped destruction.
"Planning a new and decisive assault, the Shining Ones planted atomic mines throughout the foundations of Atlantis. But the Atlanteans struck first by a matter of hours. At a set moment every volcanic vent on the Earth's surface belched forth colossal volumes of a green gas. Though that gas was harmless to creatures of Earth, it meant slow but certain death to all Rikorians. Furiously the Shining Ones struck their own blow, setting off the cataclysmic explosion that sank Atlantis forever beneath the waters of the Atlantic. Scarcely a handful of Atlanteans escaped, but Rikor's victory was a hollow one. Earth's air was so thoroughly poisoned that it would require centuries of slow ionization by sunlight to again make it fit for Rikorian breathing. The Shining Ones had at most three months before the slow poison would weaken their bodies to the danger point."
"Why didn't they go back to their own planet, then, where they belonged?" broke in the truculent voice of Garrigan again.
"That was impossible," Layroh answered impatiently. "The few space ships they had left would carry barely a score, and Rikor's sun was already so far advanced in its swing away from Earth that there would be time for only one trip. There was only one chance for survival remaining to them. They knew of a process of suspended animation in which their bodies could survive almost indefinitely without being harmed by the Atlantean gas. They would require outside aid to be awakened from that dormant state, so a small group of them must remain active and embark for Rikor, to try to survive there until Rikor returned near enough to the Earth for them to again cross the void.