Faint light was filtering through my eyelids when I came back to consciousness. As I opened them I sat weakly up, then fell back. Dazedly I gazed about me. I was lying in a small, square room lit only by its own glowing walls and floor and ceiling, a room whose one side slanted steeply upward and inward, pierced by a small barred window that was the only opening. Opposite me I discerned a low door of metal bars, or grating, beyond which lay a long, glowing-walled corridor. Then all these things were suddenly blotted out by the anxious face of Hurus Hol, bending down toward me.

"You're awake!" he exclaimed, his face alight. "You know me, Ran Rarak?"

For answer I struggled again to a sitting position, aided by the arm of Dal Nara, who had appeared beside me. I felt strangely weak, exhausted, my head throbbing with racing fires.

"Where are we?" I asked, at last. "The fight in the city-I remember that-but where are we now? And where's Nal Jak?"

The eyes of my two friends met and glanced away, while I looked anxiously toward them. Then Hurus Hol spoke slowly.

"We are imprisoned in this little room in one of the great pyramids of the glowing city," he said. "And in this room you have lain for weeks, Ran Rarak."

"Weeks?" I gasped, and he nodded. "It's been almost ten weeks since we were captured there in the city outside," he said, "and for all that time you've lain here out of your head from that blow you received, sometimes delirious and raving, sometimes completely unconscious. And in all that time this dark star, this world, has been plunging on through space toward our Galaxy, and our sun, and the theft and doom of that sun. Ten more days and it passes our sun, stealing it from the Galaxy. And I, who have learned at last what forces are behind it all, lie prisoned here.

"It was after we four were brought to this cell, after our capture, that I was summoned before our captors, before a council of those strange tentacle-creatures which was made up, I think, of their own scientists. They examined me, my clothing, all about me, then sought to communicate with me. They did not speak-communicating with each other by telepathy-but they strove to enter into communication with me by a projection of pictures on a smooth wall, pictures of their dark star world, pictures of our own Galaxy, our own sun-picture after picture, until at last I began to understand the drift of them, the history and the purpose of these strange beings and their stranger world.

"For ages, I learned, for countless eons, their mighty sun had flashed through the infinities of space, alone except for its numerous planets upon which had risen these races of tentacle-creatures. Their sun was flaming with life, then, and on their circling planets they had attained to immense science, immense power, as their system rolled on, a single wandering star, through the depths of uncharted space. But as the slow eons passed, the mighty sun began to cool, and their planets to grow colder and colder. At last it had cooled so far that to revive its dying fires they dislodged one of their own planets from its orbit and sent it crashing into their sun, feeding its waning flames. And when more centuries had passed and it was again cooling they followed the same course, sending another planet into it, and so on through the ages, staving off the death of their sun by sacrificing their worlds, until at last but one planet was left to them. And still their sun was cooling, darkening, dying. "For further ages, though, they managed to preserve a precarious existence on their single planet by means of artificial heat-production, until at last their great sun had cooled and solidified to such a point that life was possible upon its dark, dead surface. That surface, because of the solidified radio-active elements in it, shone always with pale light, and to it the races of the tentacle-creatures now moved. By means of great air-current projectors they transferred the atmosphere of their planet to the dark star itself and then cast loose their planet to wander off into space by itself, for its orbit had become erratic and they feared that it would crash into their own great dark star world, about which it had revolved. But on the warm, shining surface of the great dark star they now spread out and multiplied, raising their cities from its glowing rock and clinging to its surface as it hurtled on and on and on through the dark infinities of trackless space.

"But at last, after further ages of such existence, the tentacle-races saw that again they were menaced with extinction, since in obedience to the inexorable laws of nature their dark star was cooling still further, the molten fires at its center which warmed its surface gradually dying down, while that surface became colder and colder. In a little while, they knew, the fires at its center would be completely dead, and their great world would be a bitter, frozen waste, unless they devised some plan by which to keep warm its surface.

"At this moment their astronomers came forward with the announcement that their dark-star world, plunging on through empty space, would soon pass a great star-cluster or Galaxy of suns at a distance of some fifteen billion miles. They could not invade the worlds of this Galaxy, they knew, for they had discovered that upon those worlds lived countless trillions of intelligent inhabitants who would be able to repel their own invasion, if they attempted it. There was but one expedient left, therefore, and that was to attempt to jerk a sun out of this Galaxy as they passed by it, to steal a star from it to take out with them into space, which would revolve around their own mighty dark world and supply it with the heat they needed.

"The sun which they fixed on to steal was one at the Galaxy's very edge, our own sun. If they passed this at fifteen billion miles, as their course then would cause them to do, they could do nothing. But if they could change their dark star's course, could curve inward to pass this sun at some three billion miles instead of fifteen, then the powerful gravitational grip of their own gigantic world would grasp this sun and carry it out with it into space. The sun's planets, too, would be carried out, but these they planned to crash into the fires of the sun itself, to increase its size and splendor. All that was needed, therefore, was some method of curving their world's course inward, and for this they had recourse to the great gravity-condensers which they had already used to shift their own planets.

"You know that it is gravitational force alone which keeps the suns and planets to their courses, and you know that the gravitational force of any body, sun or planet, is radiated out from it in all directions, tending to pull all things toward that body. In the same way there is radiated outward perpetually from the Galaxy that combined attractive gravitational force of all its swarming suns, and a tiny fraction of this outward-radiating force, of course, struck the dark star, pulling it weakly toward the Galaxy. If more of that outward-radiating force could strike the dark star, it would be pulled toward the Galaxy with more power, would be pulled nearer toward the Galaxy's edge, as it passed.

"It was just that which their gravity-condenser accomplished. In a low pit at the heart of one of their cities this city, in fact-they placed the condenser, a mass of brilliant hemispherical ray-attracters which caused more of the Galaxy's outward-shooting attractive force to fall upon the dark star, thereby pulling the dark star inward toward the Galaxy's edge in a great curve. When they reached a distance of three billion miles from the Galaxy's edge they planned to turn off the great condenser, and their dark star would then shoot past the Galaxy's edge, jerking out our sun with it, from that edge, by its own terrific gravitational grip. If the condenser were turned off before they came that close, however, they would pass the sun at a distance too far to pull it out with them, and would then speed on out into space alone, toward the freezing of their world and their own extinction. For that reason the condenser, and the great cage-switch of the condenser, were guarded always by hovering cones, to prevent its being turned off before the right moment.

"Since then they have kept the great gravity-condenser in unceasing operation, and their dark star has swept in toward the Galaxy's edge in a great curve. Back in our own solar system I saw and understood what would be the result of that inward curve, and so we came here-and were captured. And in those weeks since we were captured, while you have lain here unconscious and raving, this dark star has been plunging nearer and nearer toward our Galaxy and toward our sun. Ten more days and it passes that sun, carrying it out with it into the darkness of boundless space, unless the great condenser is turned off before then. Ten more days, and we lie here, powerless to warn any of what forces work toward the doom of our sun!"

* * *

There was a long silence when Hurus Hol's voice had ceased-a whispering, brain-crushing silence which I broke at last with a single question.

"But Nal Jak-?" I asked, and the faces of my two companions became suddenly strange, while Dal Nara turned away. At last Hurus Hol spoke.

"It was after the tentacle-scientists had examined me." he said gently, "that they brought Nal Jak down to examine. I think that they spared me for the time being because of my apparently greater knowledge, but Nal Jak they-vivisected."

There was a longer hush than before, one in which the brave, quiet figure of the wheelman, a companion in all my service with the fleet, seemed to rise before my suddenly blurring eyes. Then abruptly I swung down from the narrow bunk on which I lay, clutched dizzily at my companions for support, and walked unsteadily to the square, barred little window. Outside and beneath me lay the city of the dark-star people, a mighty mass of pyramidal, glowing buildings, streets thronged with their dark, gliding figures, above them the swarms of the racing cones. From our little window the glowing wall of the great pyramid which held us slanted steeply down for fully five hundred feet, and upward above us for twice that distance. And as I raised my eyes upward I saw, clear and bright above, a great, far-flung field of stars-the stars of our own Galaxy toward which this world was plunging. And burning out clearest among these the star that was nearest of all, the shining yellow star that was our own sun.

I think now that it was the sight of that yellow star, largening steadily as our dark star swept on toward it, which filled us with such utter despair in the hours, the days, that followed. Out beyond the city our cruiser lay hidden in the black forest, we knew, and could we escape we might yet carry word back to the Federation of what was at hand, but escape was impossible. And so, through the long days, days measurable only by our own time-dials, we waxed deeper into an apathy of dull despair.

Rapidly my strength came back to me, though the strange food supplied us once a day by our captors was almost uneatable. But as the days fled by, my spirits sank lower and lower, and less and less we spoke to each other as the doom of our sun approached, the only change in any thing around us being the moment each twenty-four hours when the signal-horns called across the city, summoning the hordes in its streets to their four-hour sleep-period. At last, though, we woke suddenly to realization of the fact that nine days had passed since my awakening, and that upon the next day the dark star would be plunging past the burning yellow star above us and jerking it into its grip. Then, at last, all our apathy dropped from us, and we raged against the walls of our cells with insensate fury. And then, with startling abruptness, came the means of our deliverance.

* * *

For hours there had been a busy clanging of tools and machines somewhere in the great building above us, and numbers of the tentacle-creatures had been passing our barred door carrying tools and instruments toward some work being carried out overhead. We had come to pay but little attention to them, in time, but as one passed there came a sudden rattle and clang from outside, and turning to the door we saw that one of the passing creatures had dropped a thick coil of slender metal chain upon the floor and had passed on without noticing his loss.

In an instant we were at the door and reaching through its bars toward the coil, but through we each strained our arms in turn toward it the thing lay a few tantalizing inches beyond our grasp. A moment we surveyed it, baffled, fearing the return at any moment of the creature who had dropped it, and then Dal Nara, with a sudden inspiration, lay flat upon the floor, thrusting her leg out through the grating. In a moment she had caught the coil with her foot, and in another moment we had it inside examining it.

We found that though it was as slender as my smallest finger the chain was of incredible strength, and when we roughly estimated the extent of its thick-coiled length we discovered that it would be more than long enough to reach from our window to the street below. At once, therefore, we secreted the thing in a corner of the room and impatiently awaited the sleep-period, when we could work without fear of interruption.

At last, after what seemed measureless hours of waiting, the great horns blared forth across the city outside, and swiftly its streets emptied, the sounds in our building quieting until all was silence, except for the humming of a few watchful cones above the great condenser, and the deep droning of the condenser itself in the distance. At once we set to work at the bars of our window.

Frantically we chipped at the rock at the base of one of the metal bars, using the few odd bits of metal at our command, but at the end of two hours had done no more than scratch away a bare inch of the glowing stone. Another hour and we had laid bare from the rock the lower end of the bar, but now we knew that within minutes the sleep-period of the city outside would be ending, and into the streets would be swarming its gliding throngs, making impossible all attempts at escape. Furiously we worked, dripping now with sweat, until at last when our time-dials showed that less than half an hour remained to us I gave over the chipping at the rock and wrapped our chain firmly around the lower end of the bar we had loosened. Then stepping back into the cell and bracing ourselves against the wall below the window, we pulled backward with all our strength.

A tense moment we strained thus, the thick bar holding fast, and then abruptly it gave and fell from its socket in the wall to the floor, with a loud, ringing clang. We lay in a heap on the floor, panting and listening for any sound of alarm, then rose and swiftly fastened the chain's end to one of the remaining bars. The chain itself we dropped out of the window, watching it uncoil its length down the mighty building's glowing side until its end trailed on the empty glowing street far below. At once I motioned Hurus Hol to the window, and in a moment he had squeezed through its bars and was sliding slowly down the chain, hand under hand. Before he was ten feet down Dal Nara was out and creeping downward likewise, and then I too squeezed through the window and followed them, downward, the three of us crawling down the chain along the huge building's steeply sloping side like three flies.

I was ten feet down from the window, now, twenty feet, and glanced down toward the glowing, empty street, five hundred feet below, and seeming five thousand. Then, at a sudden sound from above me, I looked sharply up, and as I did so the most sickening sensation of fear I had ever experienced swept over me. For at the window we had just left, twenty feet above me, one of the tentacle-creatures was leaning out, brought to our cell, I doubted not, by the metal bar's ringing fall, his white, red-rimmed eye turned full upon me.

I heard sighs of horror from my two companions beneath me, and for a single moment we hung motionless along the chain's length, swinging along the huge pyramid's glowing side at a height of hundreds of feet above the shining streets below. Then the creature raised one of its tentacles, a metal tool in its grasp, which he brought down in a sharp blow on the chain at the window's edge. Again he repeated the blow, and again.

He was cutting the chain!