The incoming shift had a messy clean-up job to do. It was accomplished only because security men abruptly took over the work of gang bosses, and all ordinary labor on the Platform was put aside until normal operations were again possible. Even that would not have been feasible but for the walkie-talkies the security men wore. As the situation was sorted out, it was explained to them, and they relayed the news for the satisfaction of the curiosity of those who worked under them. No work—no explanation. It produced immediate and satisfactory co-operation all around.

There had been four separate and independent attempts to wreck the Platform at the same time. One was, of course, the plan of those sympathetic characters who had volunteered to help Mike and his gang win the status of spacemen by firing the Platform’s rockets. There were not many of them, and they had lost heavily. They’d had thermite bombs to destroy the Platform’s vitals. Ultimately the survivors talked freely, if morosely, and that was that.

There had been a particularly ungifted attempt to cause panic in the incoming shift in the rooms where its members were screened before admission to work. Somebody had tried to establish complete confusion there by firing revolver shots in the crowd, expecting the workers to break through to the floor and assigned gentlemen with slabs of explosive to get to the Platform with them. The gentlemen with the explosives had run into Major Holt’s security reserve, and they got nowhere. The creators of panic with revolver shots were finally rescued from their shift-mates and more or less scraped up from the screening-room floor—they were in very bad shape—and carted off to be patched up for questioning. The members of this group had been impractical idealists, and besides, some of them had lost their nerve, as was evidenced by the discovery of abandoned explosives and detonators in the locker room and men’s room of the Shed.

The most dangerous attempt was, of course, that perfectly planned and co-ordinated assault which had been merely carried out at its original time, without either being hastened or delayed by Mike’s activities. That plan had been beautifully contrived, and it would certainly have been successful but for the machine-gun bullets from the gallery and the fight Joe’s followers put up underneath the Platform.

The exact instant when the whole Shed would be most nearly empty had been fixed upon, and three separate units had worked in perfect timing. There’d been the man in the stalled truck. He’d delayed his exit from the Shed to the precise fraction of a second to get the doors open at the perfect instant. The explosive-laden trucks had raced in at the exact second when they were most certain to get underneath the Platform and detonate their cargoes. There’d been a perfect diversion planned for that, too. Smoke bombs and explosions in the outgoing screening rooms had created real panic, and but for Joe’s order for his group’s walkie-talkies to be turned off would have drawn every security man on duty to that spot.

Mike’s trick, then, had brought some saboteurs into the open, but had merely happened to coincide with the most dangerous and well-organized coup of all. However, it was due to his trick that the Platform was not now a wreck.

There was also another break that was sheer coincidence. It was a discovery that could not possibly have turned up save in a situation of pure chaos artificially induced. Joe had had to react in a personal and vengeful way to the manner in which his especial antagonist had fought him. One expects a man to fight fair by instinct, and to turn to fouls—if he does—in desperation only. But Joe’s personal opponent hadn’t tried a single fair trick. It was as if he’d never heard of a fist blow, but only of murder and mayhem. Joe felt an individual enmity toward him.

Joe didn’t consider himself the most urgent of the injured, when doctors and nurses took up the work of patching, but Sally was there to help, and she went deathly pale when she saw his bloodstained throat. She dragged him quickly to a doctor. And the doctor looked at Joe and dropped everything else.

But it wasn’t too serious. The antiseptics hurt, and the stitching was unpleasant, but Joe was more worried by the knowledge that Sally was standing there and suffering for him. When he got up from the emergency operating table, the doctor nodded grimly to him.

“That was close!” said the doctor. “Whoever chewed you was working for your jugular vein, and he was halfway through the wall when he stopped. A fraction of an inch more, and he’d have had you!”

“Thanks,” said Joe. His neck felt clumsy with bandages, and when he tried to turn his head the stitches hurt.

Sally’s hand trembled in his when she led him away.

“I didn’t think I’d ever dislike anybody so much,” said Joe angrily, “as I did that man while he was chewing my throat. We were trying to kill each other, of course, but—confound it, people don’t bite!”

“Did you—kill him?” asked Sally in a shaky voice. “Not that I’ll mind! I would have hated the thought ordinarily, but——”

Joe halted. There was a row of stretchers—not too long, at that—in the emergency-hospital space. He looked down at the unconscious man who’d fought him.

“There he is!” he said irritably. “I banged him pretty hard. I don’t like to hate anybody, but the way he fought——”

Sally’s teeth chattered suddenly. She called to one of the security men standing guard by the stretchers.

“I—think my—father is going to want to talk to him,” she said unsteadily. “Don’t—let him be taken away to the hospital until Dad knows, please.”

She started away, her face dead-white and her hand stone-cold.

“What’s the matter?” demanded Joe.

“S-sabotage,” said Sally in an indescribable tone that had a suggestion of heartbreak.

She went into her father’s office alone. She came out again with him, and her father looked completely stricken. Miss Ross, his secretary, was with him, too. Her face was like a mask of marble. She had always been a plain woman, a gloomy one, a morbid one. But at the new and horrible look on her face Joe turned his eyes away.

Then Sally was crying beside him, and he put his arm clumsily around her and let her sob on his shoulder, completely puzzled.

He didn’t find out until later what the trouble was. The man who’d tried so earnestly to kill him was Miss Ross’s fiancÉ. She had met this man during a vacation, as a government secretary, and he was a refugee with an exotic charm that would have fascinated a much more personable and beautiful woman than Miss Ross. They had a whirlwind romance. He confided to her his terror of emissaries from his native country who might kill him. And of course she was more fascinated still. When he asked her to marry him she accepted his proposal. Then, just two weeks before her assignment to the Space Platform project, he vanished. Miss Ross was desperate and lovesick.

One day her telephone rang and his anguished voice told her he’d been abducted, and if she told the police he would be tortured to death. He begged her not to do anything to cause him more torment than was already his.

She’d been trying to keep him alive ever since. Once, when she couldn’t bring herself to carry out an order she’d been given—with threats of torment to him if she failed—she’d received a human finger in the mail, and a scrawled and blood-stained note which cried out of unspeakable torment and begged her not to doom him to more.

So Miss Ross, who was Major Holt’s secretary and one of his most trusted assistants, had been giving information to one group of saboteurs all the while. She was the most dangerous security leak in the whole Platform project.

But her fiancÉ wasn’t a captive. He was the head of that group of saboteurs. He’d made love to her and proposed to her merely to prepare her to supply the information he wanted. He needed only to write a sufficiently agonized note, or gasp tormented pleas on a telephone, to get what he wanted.

Incidentally, he still had all his fingers when Joe knocked him cold.

Sally had recognized him as the subject of a snapshot she’d once seen Miss Ross crying over. Miss Ross had hidden it hastily and told her it was someone she had once loved, now dead. And this inadvertent disclosure that Miss Ross was the security leak the Major had never had a clue to could only have come about through such confusion as Mike had instigated and Haney and the Chief and Joe had organized. But Joe learned those facts only later.

At the moment, there was still the Platform to be gotten aloft. And there was plenty of work to do. There were two small rips in the plating, caused by fragments of the exploded truck. There were some bullet holes. The Platform could resist small meteorites at forty-five miles a second, but a high-velocity small-arm projectile could puncture it. Those scars of battle had to be welded shut. The rest of the scaffolding had to come down and the rest of the rocket tubes had to be affixed. And there was cleaning up to be done.

These things occupied the shift that came on at the time of the multiple sabotage assaults. At first the work was ragged. But the policy of turning the Security men into news broadcasters worked well. After all, the Platform was a construction job and the men who worked on it were not softies. Most of them had seen men killed before. Before the shift was half over, a definite work rhythm was evident. Men had begun to take an even greater pride in the thing they had built, because it had been assailed and not destroyed. And the job was almost over.

Sally went back to her father’s quarters, to try to sleep. Joe stayed in the Shed. His throat was painful enough so that he didn’t want to go to bed until he was genuinely tired, and he was thoroughly wrought up.

Mike the midget had gone peacefully to sleep again, curled up in a corner of the outgoing screening room. His fellow midgets talked satisfiedly among themselves. Presently, to show their superiority to mere pitched battles, two of them brought out a miniature pack of cards and started a card game while they waited for a bus to take them back to Bootstrap.

The Chief’s Indian associates loafed comfortably while waiting for the same busses. Later they would put in for overtime—and get it. Haney mourned that he had been remote from the scene of action, and was merely responsible for the presence and placing and firing of the machine guns that had certainly kept the Platform from being blown up from below.

It seemed that nothing else would happen to bother anybody. But there was one thing more.

That thing happened just two hours before it was time for the shift to change once again, and when normal work was back in progress in the Shed. Everything seemed fully organized and serene. Everything in the Shed had settled down, and nothing had happened outside.

There was ample exterior protection, of course, but the outside-guard system hadn’t had anything to do for a very long time. Men at radar screens were bored and sleepy from sheer inactivity and silence. Pilots in jet planes two miles and five miles and eight miles high had long since grown weary of the splendid view below them. After all, one can get very used to late, slanting moonlight on cloud masses far underneath, and bright and hostile-seeming stars overhead.

So the thing was well timed.

A Canadian station noticed the pip on its radar screen first. The radar observer was puzzled by it. It could have been a meteor, and the Canadian observer at first thought it was. But it wasn’t going quite fast enough, and it lasted too long. It was traveling six hundred seventy-two miles an hour, and it was headed due south at sixty thousand feet. The speed could have been within reason—provided it didn’t stay constant. But it did. There was something traveling south at eleven miles a minute or better. A mile in five-plus seconds. It didn’t slow. It didn’t drop.

The Canadian radarman debated painfully. He stopped his companion from the reading of a magazine article about chinchilla breeding in the home. He showed him the pip, still headed south and almost at the limit of this radar instrument’s range. They discussed the thing dubiously. They decided to report it.

They had a little trouble getting the call through. The night long-distance operators were sleepy. Because of the difficulty of making the call, the radarmen became obstinate and insisted on putting it through. They reported to Ottawa that some object flying at sixty thousand feet and six hundred seventy-two miles an hour was crossing Canada headed for the United States.

There was a further time loss. Somebody in authority had to be awakened, and somebody had to decide that a further report was justified. Then the trick had to be accomplished, and a sleepy man in a bathrobe and slippers listened and said sleepily, “Oh, of course you’ll tell the Americans. It’s only neighborly!” and padded back to his bed to go to sleep again. Then he waked up suddenly and began to sweat. He’d realized that this might be the beginning of atomic war. So he set phone bells to jangling furiously all over Canada, and jet planes began to boom in the darkness.

But there was only one object in the sky. Over the Dakotas it went higher. It went to seventy thousand feet, and then eighty. How this was managed is not completely known, because there are still some details of that flight that have never been completely explained. But certainly jatos flared briefly at some point, and the object reached ninety thousand feet where a jet motor would certainly be useless. And then, almost certainly, rockets flared once more and well south of the Dakotas it started down in a trajectory like that of an artillery shell, but with considerably higher speed than most artillery shells achieve.

It was at about this time that the siren in the Shed began its choppy, hiccoughing series of warm-up notes. The news from Canada arrived, as a matter of fact, some thirty seconds after the outer-perimeter radar screen around the Platform gave its warning. Then there was no hesitation or delay at all. Men were already tumbling out of bed at three airfields, buckling helmets and hoping their oxygen tanks would function properly. Then the radars atop the Shed itself picked up the moving speck. And small blue-white flames began to rise from the ground and go streaking away in the darkness in astonishing numbers.

The covers of the guns at the top of the Shed slid aside. Miles away, jet planes shot skyward, and newly wakened pilots looked at their night-fighting instruments and swore unbelievingly at the speed they were told the plunging object was making. The jet pilots gave their motors everything they could take, but it didn’t look good.

The planes of the jet umbrella over the Shed stopped cruising and sprinted. And they were the only ones likely to get in front of the object in time.

Inside the Shed, the siren howled dismally and all the Security men were snapping: “Radar alarm! All out! Radar alarm! All out!”

And men were moving fast, too. Some came down from the Platform on hoists, dropping with reckless speed to the floor level. Some didn’t wait for a turn at that. They slid down one upright, swung around the crosspiece on the level below, and slid down another vertical pipe. For a minute or more it looked as if the scaffolds oozed black droplets which slid down its pipes. But the drops were men. The floor became speckled and spotted with dots running for its exits.

The siren ceased its wailing and its noise went down and down in pitch until it was a baritone moan that dropped to bass and ceased. Then there was no sound but the men moving to get out of the Shed. There were trucks, too. Those that had been loading with dismantled scaffolding roared for the doors to get out and away. Some men jumped on board as they passed. The exit doors swung up to let them go.

But it was very quiet in the Shed, at that. There was no noise but a few fleeing trucks, and the murmur which was the voices of the Security men hurrying the work crew out. There was less to hear than went on ordinarily. And it was a long distance across the floor of the Shed.

Joe stood with his fists clenched absurdly. This could only be an air attack. An air attack could only mean an atom-bomb attack. And if there was an atom bomb dropped on the Shed, there’d be no use getting outside. It wouldn’t be merely a fission bomb. It would be a hell bomb—a bomb which used the kind of bomb that shattered Hiroshima only as a primer for the real explosive. Nobody could hope to get beyond the radius of its destruction before it hit!

Joe heard himself raging. He’d thought of Sally. She’d be in the range of annihilation, too. And Joe knew such fury and hatred—because of Sally—that he forgot everything else.

He didn’t run. He couldn’t escape. He couldn’t fight back. But because he hated, he had to do something to defy.

He found himself moving toward the Platform, his jaws clenched. It was pure, blind, instinctive defiance.

He was not the only one to have that reaction. Men running toward the sidewall exits began to get out of breath from their running. They slowed. Presently they stopped. They scowled and raged, like Joe. Some of them looked with burning eyes up at the roof of the Shed, though their thoughts went on beyond it. The security guards repeated, “Radar alarm! All out! Radar alarm! All out!”

Someone snarled, “Nuts to that!”

Joe saw a man walking in the same direction as himself. He was walking deliberately back to the Platform. Somebody else was headed back too....

Very peculiarly, almost all the men on the floor had ceased to run. They began to gather in little groups. They knew flight was useless. They talked briefly. Profanely. Here and there men started disgustedly back toward the Platform. Their lips moved in expressions of furious scorn. Their scorn was of themselves.

There was a gathering of men about the base of the framework that still partly veiled the Platform. They tended to face outward, angrily, and to clench their fists.

Then somebody started an engine. A man began to climb furiously back to where he had been at work. Quite unreasonably, other men followed him.

Hammers began defiantly and enragedly to sound.

The work crew in the Shed went defiantly and furiously back to work. A clamor was set up that was almost the normal working noise. It was the only possible way in which those men could express the raging contempt they felt for those who would destroy the thing they worked on.

But there were some other men who could do more. There were three levels of jet planes above the Shed, and they could dive. The highest one got first to the line along which the missile from an unknown place was plunging toward the Shed. That plane steadied on a collision course and let go its wing load of rockets. It peeled off and got out of the way. Seconds later the others from the jet umbrella were arriving. A tiny spray of proximity-fused rockets blazed furiously toward the invisible thing from the heights.

Other planes and yet others came hurtling to the line their radars briskly computed for them. There were more rockets....

The black-painted thing with more than the speed of an artillery shell plunged into a miniature hail of rockets. They flamed viciously. Half a dozen—a dozen—explosions that were pure futility.

Then there was an explosion that was not. Nobody saw it, because its puny detonation was instantly wiped out in a blaze of such incredible incandescence that the aluminum paint on jet planes still miles away was scorched and blistered instantly. The light of that flare was seen for hundreds of miles. The sound—later on—was heard farther still. And the desert vegetation miles below the hell bomb showed signs of searing when the morning came.

But the thing from the north was vaporized, utterly, some forty-five miles from its target. The damage it did was negligible.

The work on the preparation for the Platform’s take-off went on. When the all-clear signal sounded inside the Shed, nobody paid any attention. They were too busy.

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