The Throg task force struck the Terran Survey camp a few minutes after dawn, without warning, and with a deadly precision which argued that the aliens had fully reconnoitered and prepared that attack. Eye-searing lances of energy lashed back and forth across the base with methodical accuracy. And a single cowering witness, flattened on a ledge in the heights above, knew that when the last of those yellow-red bolts fell, nothing human would be left alive down there. His teeth closed hard upon the thick stuff of the sleeve covering his thin forearm, and in his throat a scream of terror and rage was stillborn.

More than caution kept him pinned on that narrow shelf of rock. Watching that holocaust below, Shann Lantee could not force himself to move. The sheer ruthlessness of the Throg move-in left him momentarily weak. To listen to a tale of Throgs in action, and to be an eye-witness to such action, were two vastly different things. He shivered in spite of the warmth of the Survey Corps uniform.

As yet he had sighted none of the aliens, only their plate-shaped flyers. They would stay aloft until their long-range weapon cleared out all opposition. But how had they been able to make such a complete annihilation of the Terran force? The last report had placed the nearest Throg nest at least two systems away from Warlock. And a patrol lane had been drawn about the Circe system the minute that Survey had marked its second planet ready for colonization. Somehow the beetles had slipped through that supposedly tight cordon and would now consolidate their gains with their usual speed at rooting. First an energy attack to finish the small Terran force; then they would simply take over.

A month later, or maybe two months, and they could not have done it. The grids would have been up, and any Throg ship venturing into Warlock's amber-tinted sky would abruptly cease to be. In the race for survival as a galactic power, Terra had that one small edge over the swarms of the enemy. They need only stake out their new-found world and get the grids assembled on its surface; then that planet would be locked to the beetles. The critical period was between the first discovery of a suitable colony world and the erection of grid control. Planets in the past had been lost during that time lag, just as Warlock was lost now.

Throgs and Terrans.... For more than a century now, planet time, they had been fighting their queer, twisted war among the stars. Terrans hunted worlds for colonization, the old hunger for land of their own driving men from the over-populated worlds, out of Sol's system to the far stars. And those worlds barren of intelligent native life, open to settlers, were none too many and widely scattered. Perhaps half a dozen were found in a quarter century, and of that six maybe only one was suitable for human life without any costly and lengthy adaption of man or world. Warlock was one of the lucky finds which came so seldom.

Throgs were predators, living on the loot they garnered. As yet, mankind had not been able to discover whether they did indeed swarm from any home world. Perhaps they lived eternally on board their plate ships with no permanent base, forced into a wandering life by the destruction of the planet on which they had originally been spawned. But they were raiders now, laying waste defenseless worlds, picking up the wealth of shattered cities in which no native life remained. And their hidden temporary bases were looped about the galaxy, their need for worlds with an atmosphere similar to Terra's as necessary as that of man. For in spite of their grotesque insectile bodies, their wholly alien minds, the Throgs were warm-blooded, oxygen-breathing creatures.

After the first few clashes the early Terran explorers had endeavored to promote a truce between the species, only to discover that between Throg and man there appeared to be no meeting ground at all—total differences of mental processes producing insurmountable misunderstanding. There was simply no point of communication. So the Terrans had suffered one smarting defeat after another until they perfected the grid. And now their colonies were safe, at least when time worked in their favor.

It had not on Warlock.

A last vivid lash of red cracked over the huddle of domes in the valley. Shann blinked, half blinded by that glare. His jaws ached as he unclenched his teeth. That was the finish. Breathing raggedly, he raised his head, beginning to realize that he was the only one of his kind left alive on a none-too-hospitable world controlled by enemies—without shelter or supplies.

He edged back into the narrow cleft which was the entrance to the ledge. As a representative of his species he was not impressive, and now with those shudders he could not master, shaking his thin body, he looked even smaller and more vulnerable. Shann drew his knees up close under his chin. The hood of his woodsman's jacket was pushed back in spite of the chill of the morning, and he wiped the back of his hand across his lips and chin in an oddly childish gesture.

None of the men below who had been alive only minutes earlier had been close friends of his; Shann had never known anyone but acquaintances in his short, roving life. Most people had ignored him completely except to give orders, and one or two had been actively malicious—like Garth Thorvald. Shann grimaced at a certain recent memory, and then that grimace faded into wonder. If young Thorvald hadn't purposefully tried to get Shann into trouble by opening the wolverines' cage, Shann wouldn't be here now—alive and safe for a time—he'd have been down there with the others.

The wolverines! For the first time since Shann had heard the crackle of the Throg attack he remembered the reason he had been heading into the hills. Of all the men on the Survey team, Shann Lantee had been the least important. The dirty, tedious clean-up jobs, the dull routines which required no technical training but which had to be performed to keep the camp functioning comfortably, those had been his portion. And he had accepted that status willingly, just to have a chance to be included among Survey personnel. Not that he had the slightest hope of climbing up to even an S-E-Three rating in the service.

Part of those menial activities had been to clean the animal cages. And there Shann Lantee had found something new, something so absorbing that most of the tiring dull labor had ceased to exist except as tasks to finish before he could return to the fascination of the animal runs.

Survey teams had early discovered the advantage of using mutated and highly trained Terran animals as assistants in the exploration of strange worlds. From the biological laboratories and breeding farms on Terra came a trickle of specialized aides-de-camp to accompany man into space. Some were fighters, silent, more deadly than weapons a man wore at his belt or carried in his hands. Some were keener eyes, keener noses, keener scouts than the human kind could produce. Bred for intelligence, for size, for adaptability to alien conditions, the animal explorers from Terra were prized.

Wolverines, the ancient "devils" of the northlands on Terra, were being tried for the first time on Warlock. Their caution, a quality highly developed in their breed, made them testers for new territory. Able to tackle in battle an animal three times their size, they should be added protection for the man they accompanied into the wilderness, and their wide ranging, their ability to climb and swim, and above all, their curiosity were assets.

Shann had begun contact by cleaning their cages; he ended captivated by these miniature bears with long bushy tails. And to his unbounded delight the attraction was mutual. Alone to Taggi and Togi he was a person, an important person. Those teeth, which could tear flesh into ragged strips, nipped gently at his fingers, closed without any pressure on arm, even on nose and chin in what was the ultimate caress of their kind. Since they were escape artists of no mean ability, twice he had had to track and lead them back to camp from forays of their own devising.

But the second time he had been caught by Fadakar, the chief of animal control, before he could lock up the delinquents. And the memory of the resulting interview still had the power to make him flush with impotent anger. Shann's explanation had been contemptuously brushed aside, and he had been delivered an ultimatum. If his carelessness occurred again, he would be sent back on the next supply ship, to be dismissed without an official sign-off on his work record, thus locked out of even the lowest level of Survey for the rest of his life.

That was why Garth Thorvald's act of the night before had made Shann brave the unknown darkness of Warlock alone when he had discovered that the test animals were gone. He had to locate and return them before Fadakar made his morning inspection; Garth Thorvald's attempt to get him into bad trouble had saved his life.

Shann cowered back, striving to make his huddled body as small as possible. One of the Throg flyers appeared silently out of the misty amber of the morning sky, hovering over the silent camp. The aliens were coming in to inspect the site of their victory. And the safest place for any Terran now was as far from the vicinity of those silent domes as he could get. Shann's slight body was an asset as he wedged through the narrow mouth of a cleft and so back into the cliff wall. The climb before him he knew in part, for this was the path the wolverines had followed on their two other escapes. A few moments of tricky scrambling and he was out in a cuplike depression choked with brush covered with the purplish foliage of Warlock. On the other side of that was a small cut to a sloping hillside, giving on another valley, not as wide as that in which the camp stood, but one well provided with cover in the way of trees and high-growing bushes.

A light wind pushed among the trees, and twice Shann heard the harsh, rasping call of a clak-clak—one of the bat-like leather-winged flyers that laired in pits along the cliff walls. That present snap of two-tone complaint suggested that the land was empty of strangers. For the clak-claks vociferously and loudly resented encroachment on their chosen hunting territory.

Shann hesitated. He was driven by the urge to put as much distance between him and the landing Throg ship as he could. But to arouse the attention of inquisitive clak-claks was asking for trouble. Perhaps it would be best to keep on along the top of the cliff, rather than risk a descent to take cover in the valley the flyers patrolled.

A patch of dust, sheltered by a tooth-shaped projection of rock, gave the Terran his first proof that Taggi and his mate had preceded him, for printed firmly there was the familiar paw mark of a wolverine. Shann began to hope that both animals had taken to cover in the wilderness ahead.

He licked dry lips. Having left secretly without any emergency pack, he had no canteen, and now Shann inventoried his scant possessions—a field kit, heavy-duty clothing, a short hooded jacket with attached mittens, the breast marked with the Survey insignia. His belt supported a sheathed stunner and bush knife, and seam pockets held three credit tokens, a twist of wire intended to reinforce the latch of the wolverine cage, a packet of bravo tablets, two identity and work cards, and a length of cord. No rations—save the bravos—no extra charge for his stunner. But he did have, weighing down a loop on the jacket, a small atomic torch.

The path he followed ended abruptly in a cliff drop, and Shann made a face at the odor rising from below, even though that scent meant he could climb down to the valley floor here without fearing any clak-clak attention. Chemical fumes from a mineral spring funneled against the wall, warding off any nesting in this section.

Shann drew up the hood of his jacket and snapped the transparent face mask into place. He must get away—then find food, water, a hiding place. That will to live which had made Shann Lantee fight innumerable battles in the past was in command, bracing him with a stubborn determination.

The fumes swirled up in a smoke haze about his waist, but he strode on, heading for the open valley and cleaner air. That sickly lavender vegetation bordering the spring deepened in color to the normal purple-green, and then he was in a grove of trees, their branches pointed skyward at sharp angles to the rust-red trunks.

A small skitterer burst from moss-spotted ground covering, giving an alarmed squeak, skimming out of sight as suddenly as it had appeared. Shann squeezed between two trees and then paused. The trunk of the larger was deeply scored with scratches dripping viscid gobs of sap, a sap which was a bright froth of scarlet. Taggi had left his mark here, and not too long ago.

The soft carpet of moss showed no paw marks, but he thought he knew the goal of the animals—a lake down-valley. Shann was beginning to plan now. The Throgs had not blasted the Terran camp out of existence; they had only made sure of the death of its occupiers. Which meant they must have some use for the installations. For the general loot of a Survey field camp would be relatively worthless to those who picked over the treasure of entire cities elsewhere. Why? What did the Throgs want? And would the alien invaders continue to occupy the domes for long?

Shann did not realize what had happened to him since that shock of ruthless attack. From early childhood, when he had been thrown on his own to scratch a living—a borderline existence of a living—on the Dumps of Tyr, he had had to use his wits to keep life in a scrawny and undersized body. However, since he had been eating regularly from Survey rations, he was not quite so scrawny any more.

His formal education was close to zero, his informal and off-center schooling vast. And that particular toughening process which had been working on him for years now aided in his speedy adaption to a new set of facts, formidable ones. He was alone on a strange and perhaps hostile world. Water, food, safe shelter, those were important now. And once again, away from the ordered round of the camp where he had been ruled by the desires and requirements of others, he was thinking, planning in freedom. Later (his hand went to the butt of his stunner) perhaps later he might just find a way of extracting an accounting from the beetle-faces, too.

For the present, he would have to keep away from the Throgs, which meant well away from the camp. A fleck of green showed through the amethyst foliage before him—the lake! Shann wriggled through a last bush barrier and stood to look out over that surface. A sleek brown head bobbed up. Shann put fingers to his mouth and whistled. The head turned, black button eyes regarded him, short legs began to churn water. To his gratification the swimmer was obeying his summons.

Taggi came ashore, pausing on the fine gray sand of the verge to shake himself vigorously. Then the wolverine came upslope at a clumsy gallop to Shann. With an unknown feeling swelling inside him, the Terran went down on both knees, burying both hands in the coarse brown fur, warming to the uproarious welcome Taggi gave him.

"Togi?" Shann asked as if the other could answer. He gazed back to the lake, but Taggi's mate was nowhere in sight.

The blunt head under his hand swung around, black button nose pointed north. Shann had never been sure just how intelligent, as mankind measured intelligence, the wolverines were. He had come to suspect that Fadakar and the other experts had underrated them and that both beasts understood more than they were given credit for. Now he followed an experiment of his own, one he had had a chance to try only a few times before and never at length. Pressing his palm flat on Taggi's head, Shann thought of Throgs and of their attack, trying to arouse in the animal a corresponding reaction to his own horror and anger.

And Taggi responded. A mutter became a growl, teeth gleamed—those cruel teeth of a carnivore to whom they were weapons of aggression. Danger.... Shann thought "danger." Then he raised his hand, and the wolverine shuffled off, heading north. The man followed.

They discovered Togi busy in a small cove where a jagged tangle of drift made a mat dating from the last high-water period. She was finishing a hearty breakfast, the remains of a water rat being buried thriftily against future need after the instincts of her kind. When she was done she came to Shann, inquiry plain to read in her eyes.

There was water here, and good hunting. But the site was too close to the Throgs. Let one of their exploring flyers sight them, and the little group was finished. Better cover, that's what the three fugitives must have. Shann scowled, not at Togi, but at the landscape. He was tired and hungry, but he must keep on going.

A stream fed into the cove from the west, a guide of sorts. With very little knowledge of the countryside, Shann was inclined to follow that.

Overhead the sun made its usual golden haze of the sky. A flight of vivid green streaks marked a flock of lake ducks coming for a morning feeding. Lake duck was good eating, but Shann had no time to hunt one now. Togi started down the bank of the stream, Taggi behind her. Either they had caught his choice subtly through some undefined mental contact, or they had already picked that road on their own.

Shann's attention was caught by a piece of the drift. He twisted the length free and had his first weapon of his own manufacture, a club. Using it to hold back a low sweeping branch, he followed the wolverines.

Within the half hour he had breakfast, too. A pair of limp skitterers, their long hind feet lashed together with a thong of grass, hung from his belt. They were not particularly good eating, but they were meat and acceptable.

The three, man and wolverines, made their way up the stream to the valley wall and through a feeder ravine into the larger space beyond. There, where the stream was born at the foot of a falls, they made their first camp. Judging that the morning haze would veil any smoke, Shann built a pocket-size fire. He seared rather than roasted the skitterers after he had made an awkward and messy business of skinning them, and tore the meat from the delicate bones in greedy mouthfuls. The wolverines lay side by side on the gravel, now and again raising a head alertly to test the scent on the air, or gaze into the distance.

Taggi made a warning sound deep in the throat. Shann tossed handfuls of sand over the dying fire. He had only time to fling himself face-down, hoping the drab and weathered cloth of his uniform faded into the color of the earth on which he lay, every muscle tense.

A shadow swung across the hillside. Shann's shoulders hunched, and he cowered again. That terror he had known on the ledge was back in full force as he waited for the beam to lick at him as it had earlier at his fellows. The Throgs were on the hunt....