He did not add that no one ever used emergency over-boost, even on acceptance trials, and certainly not with drives in need of overhaul. Such demands on the multi-dee generators tremendously multiplied the chance of setting up a disastrous harmonic between them and the normal-space drive which actually moved the ship.

  "Assuming we stay coherent," he went on, "I'd guesstimate that we should be able to range on them dimensionally in about two hundred hours."

  "And at that time we'll be where, dimensionally speaking?"

  "Well up into the eta band, Ma'am. And—" he frowned "—as far as I know, no one's ever used MDMs above the delta band. Gunnery isn't sure what effect that will have on the weapons."

  "It looks like we're going to find out." Santander forced herself to speak calmly. "If Colonel Leonovna is right—and I think she is—they're headed for a Takeshita Translation. I know no one's ever tested the theory, but we have to assume that's what they're doing. If so, we know where they're headed. The question is when. Comments?"

  "I'm no dimensional physicist, Ma'am," Colonel Leonovna said after a moment, "but as I understand it, that's a function of too many variables for us to predict. The mass of the vessel, the gradient curve and subjective velocity during translation, the deformation of the multi-dee . . ." She raised her hands, palms up. "All we can say is that if Takeshita's First Hypothesis is right, they'll flip backward in time when they hit the wall and go on translating backward until they hit Sol's Frankel Limit."

  "You're overlooking a few points, Milla," Miyagi said. "Like his Second Hypothesis, whether or not time is mutable, or whether or not anyone can survive a Takeshita Translation in the first place." His tone was argumentative, but he was punching keys on his console as he spoke.

  "True," Commodore Santander said, "but we have to assume they can do it unless we stop them. We can't afford to be wrong—not about this one."

  "Agreed, Ma'am." Miyagi nodded. "And Colonel Leonovna's pretty much right about the problems, but we can make a few approximations. We know the mass of an Ogre, and they'll have to balance their multi-dee deformation to match the mass-power curve of the Trollheims' multi-dees and n-drives. . . ." He tapped keys quickly, and the others sat silent to let him work undisturbed. It took several minutes, but he finally looked up with a grim expression.

  "Commodore, it's approximate as hell, but it looks like they'll hit the Frankel Limit something on the order of 40,000 years in the past. Could be closer to 90,000 if they lose the Trollheims."

  "They won't." Colonel Leonovna shook her head. "Kangas are sure-thing players," she said softly. "They'll want to be sure Homo sapiens is around."

  "Of course," Commodore Santander murmured. She sat wrapped in her thoughts for a few moments, then shook herself.

  "Captain Onslow, pass the word to the other skippers, please. If Defender goes acoherent, whoever's left has to know this is for all the marbles. Breaking off the pursuit is not an option."

  "Yes, Ma'am," Onslow said quietly.

  "Very well. I think you can stand the crews down from action stations until we reach effective MDM range, but keep your scanner sections closed up in case they try a surprise launch down-gradient."

  "Agreed, Ma'am."

  "Nick—" she turned to Miyagi "—warm up the simulator. As soon as the Captain has everybody tucked in, we'll start working on tactics." She smiled without a trace of humor. "We're not exactly the War College, but we're all humanity has at the moment.

  "Colonel." She met Leonovna's blue eyes levelly. "I hope we won't have anything for you to do, but if we do, it'll be one hell of a dogfight. Inform the squadron commanders on the other ships, then get with your planning officers. Work out the best balance you can between antishipping and antifighter ordnance loads. Then make sure every interceptor is one hundred percent. We can't afford any hangar queens."

  "Understood, Ma'am."

  "All right, people," Santander sighed, rising from her chair. "Carry on. And if you find yourself with any spare time—" she managed a wan smile "—spend it reminding God whose side He's on."

  CHAPTER TWO

  Battle Division Ninety-Two, Terran Navy, closed steadily on its foes. They had crossed the beta, gamma, delta, epsilon, and most of the zeta band without loss, but engineers hunched anxiously over their panels as the eta wall approached. The Kangas had already cracked that wall . . . and lost two cruisers doing it. The implications were not lost on BatDiv Ninety-Two.

  The commodore sat doing the only thing she could do—projecting a confidence she was far from feeling. She knew her officers knew she was pretending, but their part of the game required them to pretend they believed her anyway. The thought amused her, despite her tension, and she smiled.

  "Coming up on the wall, Commodore," Miyagi said softly, and she nodded watching BatDiv Ninety-Two's meticulous formation on her plot. For a unit which had considered itself well behind the front lines, they were doing her proud.

  "Update the next drone," she said.

  "Aye, aye, Ma'am."

  This far out dimensionally it would take weeks for a message drone to reach the nearest fleet base (assuming it made it at all), but at least someone might know what had become of BatDiv Ninety-Two if it never turned up again. And, she was forced to admit, even if they succeeded in stopping the Kangas, the odds were that none of them would ever see Terra again. Her crews were equally aware of it, she thought, and that only made her prouder of them.

  "Eta wall in ninety seconds, Ma'am."

  "Launch the drone," she ordered.

  Commodore Santander gripped the arms of her command chair and set her teeth. Breaking the wall was always rough, but at this speed and gradient, each wall had been progressively worse, and this time promised to be—

  The universe went mad. Defender's mighty bulk whipsawed impossibly, writhing in dreadful stress. Bright, searing motes spangled Santander's vision, and her heart spasmed sharply. The shock was lethal, impossible to endure . . . and over so quickly the mind scarcely had time to note it.

  She shook herself doggedly, sagging about her bones, and sensed the same reaction from her bridge crew. Then she focused on her plot once more, and a spasm worse than translation squeezed her heart.

  "Ma'am," Miyagi said hoarsely, "Protector's—"

  "I see it, Nick." She closed her eyes in grief. Three million tons of ship and nine thousand people—gone in an instant. And she'd thought Defender's drive was in worse shape than Protector's. . . .

  "Launch from Bandit Three!" her tracking officer reported suddenly. "Multiple launch!"

  "Target?" Santander demanded sharply.

  "Tracking on Sentinel, Ma'am. Scan shows eight incoming."

  Eight! That was a full load for a Trollheim's stern battery! Heavy fire, yet not heavy enough to be automatically decisive at this range—which sounded more like a Kanga's idea than a Troll's . . . thank God.

  "Deploy decoys," she ordered. "Stand by to interdict."

  "Aye, aye, Ma'am."

  Both remaining dreadnoughts vomited decoys. Each massed well under a hundred tons, with a drive of strictly limited life, but while they lasted their scan images exactly matched that of the ship which had launched them.

  Gunnery's lock on the incoming missiles was tenuous under these conditions, despite the devious scientific tricks which shifted their scan signals up a couple of levels and made them FTL for their current band, yet the idea of evasive action was laughable. It was all up to the decoys and interdiction fields, and at least they had the advantage of human technology.

  The Multi-Dimensional Missiles flashing to meet BatDiv Ninety-Two mounted no explosive warheads; they carried something far worse: small, powerful multi-dee generators of their own. They were huge—even Defender could squeeze in only twenty-four similar weapons—but they were carried despite the squeeze they put on magazine space because they were lethal to any multi-dee field. In the microsecond before contact, their onboard generators spun up to full power, and they hit their target's field
as a directly opposed surge field, inducing harmonics guaranteed to drive any target into acoherency.

  Fortunately, Kanga MDMs were stupid compared to human weapons, and these had to make a half-dozen "downstream" translations to reach Sentinel. If tracking problems afflicted BatDiv Ninety-Two's defenses, they would also force the Kangas' missiles to rely almost entirely on their homing systems, and they were bleeding energy all the way down-gradient. That lost energy would form a "bow-wave," inducing myopia in their onboard tracking systems and degrading their accuracy dramatically. It would have required the full efforts of all three Trollheims to guarantee saturation of Sentinel's defenses at this range, and that was why Santander was certain no Troll tactician had ordered this launch.

  "Interdiction fields active," Miyagi reported, and she nodded. The last-ditch interdiction fields, like all active defenses, worked best against the longer flight times of missiles chasing from astern. They were simple in concept: focused directional energy fields projected into the paths of incoming attackers. A Guardian-class dreadnought could put out ten of them, but each was relatively tiny. The trick was to drop them exactly into the attacking weapons' line of flight, and when flight time was short and gunnery's lock was weak, it was almost as much a matter of experience and intuition as computer prediction. . . .

  Three decoys vanished, and four incoming missiles went with them. Two more MDMs ran headlong into interdiction fields and disappeared into infinity. The remaining pair whizzed past Sentinel at almost the same instant—clean misses, with absolutely no chance of tracking back around at this velocity and translation gradient—and Commodore Josephine Santander realized she had been holding her breath only when she let it out. A third of the enemy's after firepower had just been expended for absolutely no result!

  "All right, Nick," she said flatly, "we should have the range in another few minutes. Dust off the tac net and kill me some Trolls."

  "Aye, aye, Ma'am!"

  BatDiv Ninety-Two continued to overhaul at close to ninety percent of light-speed, winding down its translation gradient steadily. Commodore Santander heaved a surreptitious sigh of relief as the multi-dee generators dropped back from emergency over-boost to saner power settings. Something decidedly unnatural had been done to those Kanga multi-dees to wring such performance out of them, but the higher power margin of the human generators was still sufficient—barely—to outperform them. And once they were in the same eta band level, fire control would become far more effective. . . .

  "Dropping into dimensional synchronicity—now!" Miyagi reported.

  "Gunnery, fire plan alpha!"

  "We have a second launch, Ma'am. Two launches! Bandits Two and Four are launching full salvos at Sentinel!"

  "Replenish the decoys! Stand by to interdict!"

  Five of Defender's MDMs spewed out. Kanga decoys blossomed on her plot as Sentinel spat out a second quintet of missiles, but human MDMs were smarter—and faster—than anything the Kangas had. Even in a pursuit curve, they streaked past the enemy's decoys before the return fire could range on the human lures, and she felt a savage grin stretch her lips as one group of missiles ran in on each of the two rearmost Trollheims.

  Troll reflexes were quick, but their predictors were less efficient than BatDiv Ninety-Two's. Interdiction fields destroyed seven missiles in bursts of light like brief suns—but the other three went home, and the capital ship odds were suddenly even.

  Yet sixteen Kanga MDMs still raced into the teeth of the depleted squadron's defenses. Decoys called to them and died. Interdiction fields flared with eye-stabbing intensity as they crashed into the barriers and disappeared uselessly. And one slid past everything both dreadnoughts could throw at it.

  Josephine Santander bit her lip hard as TNS Sentinel vanished into the howling depths of eternity.

  The bridge was silent with the stunned stillness of shock.

  "Abort engagement." Santander's soft command seemed shockingly loud in the silence, and Miyagi shook himself, then relayed the order quietly to the rest of her division. She closed her eyes briefly. Sentinel should have come through—but she hadn't. And without Sentinel or Protector to support her, Defender had no MDMs to waste at extended ranges. There were still nine warships in front of her, and she had only nineteen more of the big missiles.

  The commodore leaned back in her command chair, fighting the shock and grief of eighteen thousand lost lives as she grappled with the imperatives of her situation. She had Defender, one heavy cruiser, and three destroyers against four capital ships and five light cruisers. As long as she remained astern, she was safe, for the Trollheim had expended her aft MDMs and the Ogre mounted no stern battery . . . but if she stayed behind them, she gave them every defensive advantage there was.

  "Captain Onslow," she said calmly, "we'll have to get ahead of them."

  "Understood, Ma'am," the captain's voice was harsh but level. "Going back to over-boost now."

  She closed her ears to the keen of the multi-dee as it rose once more, but she could not close her thoughts. If she lost the ship now, there was no hope, for Defender was her only remaining dreadnought. Her chance of stopping the enemy was horrifyingly slim, but without her flagship, BatDiv Ninety-Two's escorts had none at all.

  "Scan reports they're trying to crank their translation fields up a bit, Ma'am," Miyagi said quietly. She opened one eye and gave him what she hoped was a confident look. "They're not getting very far; we're level-reaching on them now."

  "Good." She inhaled. "What's their formation?"

  "The heavies are moving into translation lock, and the cruisers are closing up to cover the rear of their formation, Ma'am."

  "I see." She glanced at her com screen and saw the understanding in Captain Onslow's eyes. It was a smart move, if a cold-blooded one. But then, those cruisers were crewed by Trolls. They were expendable.

  In fact, they were more expendable than her own MDMs. Above the beta band, nothing else could get through the interface of a translation field and an n-drive's field. The translation field exerted a "dimensional shear" effect on anything that tried to cross it, while the n-drive distorted the space about a vessel and distributed all the tremendous mass it built up at relativistic velocities across the surface of its field. Either alone could be handled; hitting their combined strength with anything less than an MDM was like trying to split a planet with a claw hammer.

  Once a ship dropped into the lower bands or sublight, it was another matter. But the Kangas and their Trolls wouldn't do that until they arrived at Sol, and they could not be permitted to arrive.

  Yet the threat to humanity rode in the Ogre, which was precisely why the light cruisers had dropped back between it and Defender. Their translation fields were the only ones the seekers in Defender's MDMs could now "see," and each would cost her two or three—possibly even four—MDMs to pick off. Which meant that she would run out of missiles before she even got a shot at the ship she had to destroy.

  "Time to crossover?" she asked Miyagi.

  "Forty-five minutes for translation crossover. How soon we can overhaul them spatially depends on how far we want to level-reach on them."

  "And from crossover to the theta wall at their present power curve?"

  "Another hundred and twenty hours, Ma'am."

  "All right." She sat up straight, meeting Onslow's eyes. "Captain, you will reduce drive power to maintain this spatial interval until you have attained a six level advantage, then go to full power and overhaul them. We'll have the scanner advantage for defensive fire control, and we'll just have to take our chances on level drop when we fire."

  "Yes, Ma'am. Understood."

  "Nick," she said softly to Miyagi, "close up the tin cans. Put them between us and the Kangas when we begin to overhaul."

  "Yes, Ma'am. They'll understand."

  "That doesn't make me like it," she said bleakly, then pushed her inner anguish aside. "Once we start overhauling, they'll probably shift formation to keep those cruisers in our way, but we'll
be shooting down their throats. Even with level drop, that should let us take out a cruiser with only a pair of missiles, and if we can blow them out of the way, we'll have a shot at the leader. That's all we really need. Just one good shot at him."

  "Agreed, Ma'am. But what about their translation lock?"

  She knew what he meant. By locking their multi-dees in phase, the enemy ships presented what was, in effect, a single target to Defender's MDMs. It was a colossal game of Russian roulette, for the level drop penalties meant that once her missiles were launched, Defender had no means to influence the ships they actually targeted. And just to make things more difficult, the massed defensive systems of all the targets could combine against her salvos.

  "We'll just have to do our best, Nick. It's the only game in town."

  She brooded over her plot a moment longer, then sighed.

  "All right, Commander," she said finally, "get those destroyers moving."

  CHAPTER THREE

  Commodore Santander gripped her command chair arms to still the tremble of her fingers, and her face was haunted. Fifty-three sleepless hours might explain her gaunt, hollowed cheeks, but not the ghosts behind her eyes.

  A strange and terrible tension had invaded Defender's heart, and the viscous air shimmered with a vibration as eerie as it was indefinable. It wore away at tempers and fogged minds which sought to concentrate on vital tasks, and voices sounded tinny and unnatural, falling upon the ear with a peculiar brittleness—a sense of déjà vu, as if each sentence were an echo of something which had been said but a moment before.

  She no longer tried to hide her fear. It would have been pointless, for her people all shared it, just as they shared her exhaustion. Worse, every one of them knew what she knew: the fate of the human race rested upon their shoulders . . . and they were failing.

  "All right, Steve," she said, "how bad is it?"