There were an even dozen of the air-borne guardians, each following the swing of its own orbital path just within the atmospheric envelope of the planet which glowed as a great bronze-golden gem in the four-world system of a yellow star. The globes had been launched to form a web of protection around Topaz six months earlier, and the highest skill had gone into their production. Just as contact mines sown in a harbor could close that landfall to ships not knowing the secret channel, so was this world supposedly closed to any spaceship not equipped with the signal to ward off the sphere missiles.

That was the theory of the new off-world settlers whose protection they were to be, already tested as well as possible, but as yet not put to the ultimate proof. The small bright globes spun undisturbed across a two-mooned sky at night and made reassuring blips on an installation screen by day.

Then a thirteenth object winked into being, began the encircling, closing spiral of descent. A sphere resembling the warden-globes, it was a hundred times their size, and its orbit was purposefully controlled by instruments under the eye and hand of a human pilot.

Four men were strapped down on cushioned sling-seats in the control cabin of the Western Alliance ship, two hanging where their fingers might reach buttons and levers, the others merely passengers, their own labor waiting for the time when they would set down on the alien soil of Topaz. The planet hung there in their visa-screen, richly beautiful in its amber gold, growing larger, nearer, so that they could pick out features of seas, continents, mountain ranges, which had been studied on tape until they were familiar, yet now were strangely unfamiliar too.

One of the warden-globes alerted, oscillated in its set path, whirled faster as its delicate interior mechanisms responded to the awakening spark which would send it on its mission of destruction. A relay clicked, but for the smallest fraction of a millimeter failed to set the proper course. On the instrument, far below, which checked the globe's new course the mistake was not noted.

The screen of the ship spiraling toward Topaz registered a path which would bring it into violent contact with the globe. They were still some hundreds of miles apart when the alarm rang. The pilot's hand clawed out at the bank of controls; under the almost intolerable pressure of their descent, there was so little he could do. His crooked fingers fell back powerlessly from the buttons and levers; his mouth was a twisted grimace of bleak acceptance as the beat of the signal increased.

One of the passengers forced his head around on the padded rest, fought to form words, to speak to his companion. The other was staring ahead at the screen, his thick lips wide and flat against his teeth in a snarl of rage.

"They ... are ... here...."

Ruthven paid no attention to the obvious as stated by his fellow scientist. His fury was a red, pulsing thing inside him, fed by his own helplessness. To be pinned here so near his goal, fastened up as a target for an inanimate but cunningly fashioned weapon, ate into him like a stream of deadly acid. His big gamble would puff out in a blast of fire to light up Topaz's sky, with nothing left—nothing. On the armrest of his sling-seat his nails scratched deep.

The four men in the control cabin could only sit and watch, waiting for the rendezvous which would blot them out. Ruthven's flaming anger was a futile blaze. His companion in the passenger seat had closed his eyes, his lips moving soundlessly in an expression of his own scattered thoughts. The pilot and his assistant divided their attention between the screen, with its appalling message, and the controls they could not effectively use, feverishly seeking a way out in these last moments.

Below them in the bowl of the ship were those who would not know the end consciously—save in one compartment. In a padded cage a prick-eared head stirred where it rested on forepaws, slitted eyes blinked, aware not only of familiar surroundings, but also of the tension and fear generated by human minds and emotions levels above. A pointed nose raised, and there was a growling deep in a throat covered with thick buff-gray hair.

The growl aroused another similar captive. Knowing yellow eyes met yellow eyes. An intelligence, which was certainly not that of the animal body which contained it, fought down instinct raging to send both those bodies hurtling at the fastenings of the twin cages. Curiosity and the ability to adapt had been bred into both from time immemorial. Then something else had been added to sly and cunning brains. A step up had been taken—to weld intelligence to cunning, connect thought to instinct.

More than a generation earlier mankind had chosen barren desert—the "white sands" of New Mexico—as a testing ground for atomic experiments. Humankind could be barred, warded out of the radiation limits; the natural desert dwellers, four-footed and winged, could not be so controlled.

For thousands of years, since the first southward roving Amerindian tribes had met with their kind, there had been a hunter of the open country, a smaller cousin of the wolf, whose natural abilities had made an undeniable impression on the human mind. He was in countless Indian legends as the Shaper or the Trickster, sometimes friend, sometimes enemy. Godling for some tribes, father of all evil for others. In the wealth of tales the coyote, above all other animals, had a firm place.

Driven by the press of civilization into the badlands and deserts, fought with poison, gun, and trap, the coyote had survived, adapting to new ways with all his legendary cunning. Those who had reviled him as vermin had unwillingly added to the folklore which surrounded him, telling their own tales of robbed traps, skillful escapes. He continued to be a trickster, laughing on moonlit nights from the tops of ridges at those who would hunt him down.

Then, close to the end of the twentieth century, when myths were scoffed at, the stories of the coyote's slyness began once more on a fantastic scale. And finally scientists were sufficiently intrigued to seek out this creature that seemed to display in truth all the abilities credited to his immortal namesake by pre-Columbian tribes.

What they discovered was indeed shattering to certain closed minds. For the coyote had not only adapted to the country of the white sands; he had evolved into something which could not be dismissed as an animal, clever and cunning, but limited to beast range. Six cubs had been brought back on the first expedition, coyote in body, their developing minds different. The grandchildren of those cubs were now in the ship's cages, their mutated senses alert, ready for the slightest chance of escape. Sent to Topaz as eyes and ears for less keenly endowed humans, they were not completely under the domination of man. The range of their mental powers was still uncomprehended by those who had bred, trained, and worked with them from the days their eyes had opened and they had taken their first wobbly steps away from their dams.

The male growled again, his lips wrinkling back in a snarl as the emanations of fear from the men he could not see reached panic peak. He still crouched, belly flat, on the protecting pads of his cage; but he strove now to wriggle closer to the door, just as his mate made the same effort.

Between the animals and those in the control cabin lay the others—forty of them. Their bodies were cushioned and protected with every ingenious device known to those who had placed them there so many weeks earlier. Their minds were free of the ship, roving into places where men had not trod before, a territory potentially more dangerous than any solid earth could ever be.

Operation Retrograde had returned men bodily into the past, sending agents to hunt mammoths, follow the roads of the Bronze Age traders, ride with Attila and Genghis Khan, pull bows among the archers of ancient Egypt. But Redax returned men in mind to the paths of their ancestors, or this was the theory. And those who slept here and now in their narrow boxes, lay under its government, while the men who had arbitrarily set them so could only assume they were actually reliving the lives of Apache nomads in the wide southwestern wastes of the late eighteenth and early nineteenth centuries.

Above, the pilot's hand pushed out again, fighting the pressure to reach one particular button. That, too, had been a last-minute addition, an experiment which had only had partial testing. To use it was the final move he could make, and he was already half convinced of its uselessness.

With no faith and only a very wan hope, he sent that round of metal flush with the board. What followed no one ever lived to explain.

On the planet the installation which tracked the missiles flashed on a screen bright enough to blind momentarily the duty man on watch, and its tracker was shaken off course. When it jiggled back into line it was no longer the efficient eye-in-the-sky it had been, though its tenders were not to realize that for an important minute or two.

While the ship, now out of control, sped in dizzy whirls toward Topaz, engines fought blindly to stabilize, to re-establish their functions. Some succeeded, some wobbled in and out of the danger zone, two failed. And in the control cabin three dead men spun in prisoning seats.

Dr. James Ruthven, blood bubbling from his lips with every shallow breath he could draw, fought the stealthy tide of blackness which crept up his brain, his stubborn will holding to rags of consciousness, refusing to acknowledge the pain of his fatally injured body.

The orbiting ship was on an erratic path. Slowly the machines were correcting, relays clicking, striving to bring it to a landing under auto-pilot. All the ingenuity built into a mechanical brain was now centered in landing the globe.

It was not a good landing, in fact a very bad one, for the sphere touched a mountain side, scraped down rocks, shearing away a portion of its outer bulk. But the mountain barrier was now between it and the base from which the missiles had been launched, and the crash had not been recorded on that tracking instrument. So far as the watchers several hundred miles away knew, the warden in the sky had performed as promised. Their first line of defense had proven satisfactory, and there had been no unauthorized landing on Topaz.

In the wreckage of the control cabin Ruthven pawed at the fastenings of his sling-chair. He no longer tried to suppress the moans every effort tore out of him. Time held the whip, drove him. He rolled from his seat to the floor, lay there gasping, as again he fought doggedly to remain above the waves—those frightening, fast-coming waves of dark faintness.

Somehow he was crawling, crawling along a tilted surface until he gained the well where the ladder to the lower section hung, now at an acute angle. It was that angle which helped him to the next level.

He was too dazed to realize the meaning of the crumpled bulkheads. There was a spur of bare rock under his hands as he edged over and around twisted metal. The moans were now a gobbling, burbling, almost continuous cry as he reached his goal—a small cabin still intact.

For long moments of anguish he paused by the chair there, afraid that he could not make the last effort, raise his almost inert bulk up to the point where he could reach the Redax release. For a second of unusual clarity he wondered if there was any reason for this supreme ordeal, whether any of the sleepers could be aroused. This might now be a ship of the dead.

His right hand, his arm, and finally his bulk over the seat, he braced himself and brought his left hand up. He could not use any of the fingers; it was like lifting numb, heavy weights. But he lurched forward, swept the unfeeling lump of cold flesh down against the release in a gesture which he knew must be his final move. And, as he fell back to the floor, Dr. Ruthven could not be certain whether he had succeeded or failed. He tried to screw his head around, to focus his eyes upward at that switch. Was it down or still stubbornly up, locking the sleepers into confinement? But there was a fog between; he could not see it—or anything.

The light in the cabin flickered, was gone as another circuit in the broken ship failed. It was dark, too, in the small cubby below which housed the two cages. Chance, which had snuffed out nineteen lives in the space globe, had missed ripping open that cabin on the mountain side. Five yards down the corridor the outside fabric of the ship was split wide open, the crisp air native to Topaz entering, sending a message to two keen noses through the combination of odors now pervading the wreckage.

And the male coyote went into action. Days ago he had managed to work loose the lower end of the mesh which fronted his cage, but his mind had told him that a sortie inside the ship was valueless. The odd rapport he'd had with the human brains, unknown to them, had operated to keep him to the old role of cunning deception, which in the past had saved countless of his species from sudden and violent death. Now with teeth and paws he went diligently to work, urged on by the whines of his mate, that tantalizing smell of an outside world tickling their nostrils—a wild world, lacking the taint of man-places.

He slipped under the loosened mesh and stood up to paw at the front of the female's cage. One forepaw caught in the latch and pressed it down, and the weight of the door swung against him. Together they were free now to reach the corridor and see ahead the subdued light of a strange moon beckoning them on into the open.

The female, always more cautious than her mate, lingered behind as he trotted forward, his ears a-prick with curiosity. Their training had been the same since cubhood—to range and explore, but always in the company and at the order of man. This was not according to the pattern she knew, and she was suspicious. But to her sensitive nose the smell of the ship was an offense, and the puffs of breeze from without enticing. Her mate had already slipped through the break; now he barked with excitement and wonder, and she trotted on to join him.

Above, the Redax, which had never been intended to stand rough usage, proved to be a better survivor of the crash than most of the other installations. Power purred along a network of lines, activated beams, turned off and on a series of fixtures in those coffin-beds. For five of the sleepers—nothing. The cabin which had held them was a flattened smear against the mountain side. Three more half aroused, choked, fought for life and breath in a darkness which was a mercifully short nightmare, and succumbed.

But in the cabin nearest the rent through which the coyotes had escaped, a young man sat up abruptly, looking into the dark with wide-open, terror-haunted eyes. He clawed for purchase against the smooth edge of the box in which he had lain, somehow got to his knees, weaving weakly back and forth, and half fell, half pushed to the floor where he could stand only by keeping his hold on the box.

Dazed, sick, weak, he swayed there, aware only of himself and his own sensations. There were small sounds in the dark, a stilled moan, a gasping sigh. But that meant nothing. Within him grew a compulsion to be out of this place, his terror making him lurch forward.

His flailing hand rapped painfully against an upright surface which his questing fingers identified hazily as an exit. Unconsciously he fumbled along the surface of the door until it gave under that weak pressure. Then he was out, his head swimming, drawn by the light behind the wall rent.

He progressed toward that in a scrambling crawl, making his way over the splintered skin of the globe. Then he dropped with a jarring thud onto the mound of earth the ship had pushed before it during its downward slide. Limply he tumbled on in a small cascade of clods and sand, hitting against a less movable rock with force enough to roll him over on his back and stun him again.

The second and smaller moon of Topaz swung brightly through the sky, its weird green rays making the blood-streaked face of the explorer an alien mask. It had passed well on to the horizon, and its large yellow companion had risen when a yapping broke the small sounds of the night.

As the yipp, yipp, yipp arose in a crescendo, the man stirred, putting one hand to his head. His eyes opened, he looked vaguely about him and sat up. Behind him was the torn and ripped ship, but he did not look back at it.

Instead, he got to his feet and staggered out into the direct path of the moonlight. Inside his brain there was a whirl of thoughts, memories, emotions. Perhaps Ruthven or one of his assistants could have explained that chaotic mixture for what it was. But for all practical purposes Travis Fox—Amerindian Time Agent, member of Team A, Operation Cochise—was far less of a thinking animal now than the two coyotes paying their ritual addresses to a moon which was not the one of their vanished homeland.

Travis wavered on, drawn somehow by that howling. It was familiar, a thread of something real through all the broken clutter in his head. He stumbled, fell, crawled up again, but he kept on.

Above, the female coyote lowered her head, drew a test sniff of a new scent. She recognized that as part of the proper way of life. She yapped once at her mate, but he was absorbed in his night song, his muzzle pointed moonward as he voiced a fine wailing.

Travis tripped, pitched forward on his hands and knees, and felt the jar of such a landing shoot up his stiffened forearms. He tried to get up, but his body only twisted, so he landed on his back and lay looking up at the moon.

A strong, familiar odor ... then a shadow looming above him. Hot breath against his cheek, and the swift sweep of an animal tongue on his face. He flung up his hand, gripped thick fur, and held on as if he had found one anchor of sanity in a world gone completely mad.

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