Tranquility's Heirs

Part Four

Kris ventures into the heart of the moonbase

This science fiction novel was originally written many decades ago. The computers may be described as AI but that term did not exist back then. Let's be kind. There is very little sex and only minor nudity, so it can't be described as erotic. But it is a love story that builds over time. All characters are over 18 years old. All rights reserved by the author.

Recap; allowed access the landing bays, New Ranger's crew is planning their next more. Kris has been given permission to visit the community level in search of medical supplies.

* * * * * *

Chapter 4

AMBUSH!

Several kilometers to the west, three moonwalkers struggled to place a sled underneath their crippled shuttlecraft. The procedure wasn't going well, the tripod sling unable to raise the shuttle from the gravelly bed.

"Without another meter for clearance, this fucking thing ain't goin' no place," Mike grunted through the intercom. "Can we hike the apex another notch or two?"

"Michael? Why don't you just admit you don't know how to operate the lift?" Valerie asked in exasperation.

"Never admit the obvious, honey," he answered.

They made another inspection of the shuttlecraft's front end where the nose bent into the hillside, probing for a way to make space for the sled. Occasionally, they'd pause to gaze out over the plains of Mare Tranquillitatis to the south and west, the vast rolling landscape dotted by craters and rills.

"I'm sure we've got the right idea," Kris said. "Making the apex a little higher might help, but we still need more draw from the pulley. Either that or get shovels and start digging."

"Hell, it'll take two days to trench this out!" Mike said. "How about rigging a drag cable? We can lift her rear end with a jack and yank her backward with a tow line."

"Might work, if you don't mind starting from scratch," Kris said.

"Damn it! Got any better ideas?" Mike asked.

"There were several other tractors in the landing bay garage. Maybe we can find one with a more powerful wrench?" Valerie suggested.

"I'm not making any unnecessary treks," Mike complained. "I hate those airlocks. It's like we're being watched or something."

"But if we need the equipment, the trek won't be unnecessary," Valerie said impatiently. "And there's nothing wrong with the airlocks. An extra couple hours on the surface isn't going to hurt you."

"We're wasting our time," Mike said. "Regardless of what we do, this bird will never fly again. Bottom's all torn up."

"You're the one wasting our time," Kris said. "We're lucky she's intact at all. The sentinel said the ship's repairable and I agree. Now if we aren't going to drag her out of this pit today, we may as well pack up our supplies and go back for more gear."

"Yeah, okay. No reason to get huffy. You're the one getting all the special privileges," Mike said.

"Hush up, Michael. You're being rude," Valerie scolded.

"Fry my ass," he growled.

"You two fight it out," Kris said, anxious to escape the crossfire. "I'll climb up top and start handing stuff down."

"That's a good idea," Valerie agreed, kicking moon dust on Mike's boots and turning her back on him.

Kris scrambled up the side of the shuttlecraft and disappeared into the upper airlock, reappearing a moment later with several containers.

"What should we bring in first?" Kris asked.

"Food! I'm not eating anything I don't recognize," Mike said.

Kris laughed and attached a line on the refrigerated food unit, preparing to lower it down the side of the shuttle, but a visual disturbance on the horizon caught her attention.

"Mike! Val! Look!" Kris called out, pointing to the east.

Not obvious at first, a moving dust cloud gradually shimmered above the ridge. Within minutes, a heavy six wheeled tractor rolled over the top of the slope and down toward their position, coming to a halt near the crashed shuttle. The glistening silver figure of the sentinel was visible in the cab.

"Greetings, humans," the sentinel announced with a strong transmission signal, jumping to the ground with a thick bounce. "This unit has been informed of your logistics problem."

"Nothing we can't handle," Mike said.

"But we appreciate your help just the same," Valerie immediately added. "We're not getting enough lift."

"Unsurprising," the sentinel said, walking slowly around the tripod with evident disapproval while Kris and Valerie tagged behind.

"Mike was saying a drag cable might give us more lift," Valerie suggested. "Maybe we can--"

"Silence human," the sentinel instructed.

"God, I wish you'd said that an hour ago," Mike chimed in.

"I don't think we need to start over," Kris said, following the sentinel closely. "Maybe we can just reposition the tripod a little?"

Without comment, the sentinel ducked under the sling to examine the braces, then suddenly began to kick the lowest tripod in a fashion that seemed most unwise. Kris jumped back, holding her breath as the apparatus shifted.

"The structure is sound," the sentinel announced, crawling out from under the hull. "Repositioning the tripods will be unnecessary. There's a rolling jack and station block in the T.L.V. I shall place a lift under the main thruster housing, then swing your craft through a teetering-V onto the sled with the wench. The operation will take forty-seven minutes."

"Sure it won't take forty-eight?" Mike asked, flinching as Valerie slapped him on the helmet.

Forty-two minutes later, the shuttlecraft was safely mounted on the sled ready to be secured. Even Mike had to admit the sentinel's method worked better than anything he would have thought of, and faster than predicted. Apparently the sentinel hadn't expected help, nor especially wanted any. Nevertheless, Kris made a nuisance of herself by insisting on a team effort. Eventually, much to her satisfaction, the sentinel let her and Mike stabilize the wench and guide pulleys.

Valerie gladly retired to a large rock and watched from a distance, studying the sentinel's movements, wondering what sort of mechanism could explain such unique agility. Long before they finished, she knew, right down to the gender and approximate age. Not a bad disguise, she thought, though hardly sophisticated enough to survive prolonged observation.

Valerie decided to say nothing of her discovery until speaking with Laureen. In retrospect, she realized McKinsey must already know. But how long had she known? Had she kept the terrible secret locked away for many years? Valerie intended to find out, but in the meantime, the awkward interaction between Kris and the sentinel was amusing to watch.

"Secure the couplings and clear for towing," the sentinel announced, telescoping the last of the tripod mount. "Use the T.L.V., it has more power than that trash hauler you brought."

Mike chafed as Valerie laughed. She had warned him the survey tractor was too light.

"Thanks for the help," Kris said, unclipping her end of the sling and emerging from the other side of the shuttle.

But the sentinel was gone. Without a word, their host had bounced up the ridge toward the base at high speed, a wispy trail of dust kicked from the rock-strewn hillside.

"See you later," Kris said with barely a backward glance, accelerating up the hill in the sentinel's wake. Mike watched them for a minute, then began securing the couplings. To make amends, Valerie jumped down to help.

"What is that thing? It's not like any robot I ever saw," Mike said. "And what's with Kris?"

"I don't know. It's not even spring," Valerie said with a suppressed smile.

"Not what?"

"Are you going to work or talk, honey? I thought you wanted to get back early."

"That I do," he agreed, patting her backside through the heavy walker. "Maybe this time we'll get some sleep."

"No trapeze this time?" she smirked.

By the time Kris reached the top of the hill and worked her way around the solar collectors, she saw little chance of catching the sentinel. For something so clumsy looking, it moved with incredible speed, each skipping bounce exploiting forward momentum with maximum efficiency.

"Hey! Wait!" Kris called out.

The sentinel continued at a steady pace down through the shallow flat, then cut to the northeast, taking advantage of a natural path to climb the slope. Kris didn't give up, pressing her pursuit until she was feeling the stress on her e.s. system. When the sentinel finally paused at the top of a flat ridge, Kris smiled and hurried to catch up, only to frown as the sentinel took off again.

They soon crossed over another ridge, bypassed landing bay major, and skirted the shattered control tower before climbing a gentle hill where the White Towers were perched upon a knoll below the towering cliff. Several times the sentinel slowed down, giving Kris hope, but then sped up again, as if testing her endurance. Kris was determined not to fail.

After a final breathless sprint, Kris reached the entrance to the White Towers where the sentinel waited for her, the wide veranda providing a panoramic view of Tranquility and the surrounding area.

"Pretty fast, aren't you?" Kris wheezed, boosting her oxygen level still higher.

"Affirmative," the sentinel replied with a labored tone.

"What are we doing now?"

"Resting."

"Then what?" she asked. "Can we explore the White Towers? I've read about the museum on National Geographic. And the towers are the tallest inhabitable structures on the moon."

"I have no use for them," the sentinel responded.

"What do you mean?"

"The White Towers serve no useful function," the sentinel explained. "Observation is better from the cliff. The external structure is unacceptably exposed. The Towers are scheduled for demolition."

"But they're beautiful!" Kris protested. "Everybody knows about the White Towers! They're like the Eiffel Tower or Pinnacle of Freedom! You can't destroy them!"

"At ease, human," the sentinel commanded. "The towers will not be harmed. Threatening to demolish them is a traditional initiation for newcomers to Tranquility. A rite of passage."

The sentinel turned to scan the plains west of the colony, the crest of Plinius barely visible on the far horizon. To the south, Jansen highlighted the road to the Apollo landing sites, the areas now fenced off historical landmarks. The planet Earth loitered high above them, the vivid colors contrasting with the star speckled backdrop.

"I didn't know it would be like this," Kris sighed. "I thought the moon was just a big dry rock in space dotted by a few dilapidated bunkers."

"Why did you come?" the sentinel asked.

"Had to. Wanted to, I guess. I couldn't stay behind with Val and Mike coming. Besides, there's not much left for me back there." Kris discovered the sentinel observing her and felt somewhat embarrassed. "I don't know why I'm telling you this. I'm sure it can't be of much interest."

"This unit is programmed for a wide variety of interests," the sentinel said, turning from the railing. "Come. Visit the White Towers you have traveled so far to see."

They entered the ground floor through a wide arch to find a unique open environment museum, the marble rotunda decorated with murals, display cases and artifacts.

"Our exhibition hall at M.I.S.T. has one of these," Kris said, leaning over a relief map of the colony. The detailed map showed the rocky spur called Tranquility Ridge that angled south from the mineral rich crater Vitruvius. On the west side of the spur, the White Towers complex and various support applications filled the area below the cliff. On the east side, a biosphere, observatory and auxiliary power station were located beyond a secondary rill. Crowning Tranquility Ridge, a small fortress was armed with VLM silos and guardian launchers. Roads spread out from the colony in all directions, the gravel highways accessing a web of connecting facilities.

"I knew Tranquility was the capital of the moon, but I had no idea it was such an industrial center, too," Kris said.

"Tranquility is still the capital of the moon," the sentinel said.

On the wall behind her, Kris admired the famous Holbern presentation of the first Apollo moon landing, the multi-dimensional depths so enticing she could almost walk in and hold the ladder for astronaut Armstrong. Nearby, a picture of her father accompanied a photovision of the colony though various stages of construction, the sequence beginning in 2026 when the first underground cavern was carved.

The display cases set against the walls held ticket stubs and souvenirs from the legendary '40 Lunar Olympics along with casts of notable footprints and relics of historic events. Kris laughed when she found the great Golden Boulder of Vitruvius locked tightly behind an impressive theft-proof screen, wondering how anyone could expect to steal a twelve-kilogram gemstone from the moon.

The layout of the museum was so casual, the arrangements so familiar, that Kris forgot she was viewing the exhibits from a walker until she followed the sentinel out through the rear portico.

"Now where are we going?" she asked, hustling after her accelerating host.

The open decking behind the White Towers, where tourists had once gathered to gape at the towering ridge, accessed a suspension bridge built over a depression at the base of the cliff. Beyond the bridge, Kris recognized the familiar columned edifice of Lunar Stadium, the multi-purpose facility carved from an outcropping of solid rock. By the time she crossed the bridge and walked through the entrance, the sentinel was already down on the playing field bouncing on the artificial turf.

"Mike would really love this," Kris said, skipping down a long flight of stairs.

"Perhaps, in a few years, he will be able to," the sentinel said.

"In a few years?"

"Tranquility must be reopened. There is much to do."

"Why in a few years?" Kris asked. "Why not now?"

"Inappropriate timing. Had your expedition waited another six months, the situation would be different."

"What situation? You know, I haven't the vaguest idea what's going on here. Why are we limited to the landing bay? Why is security so strict?"

"Explanations are unnecessary," the sentinel said.

"Well, I wish someone would explain it to me!" Kris complained. "Laureen's been a little short on specifics, and I don't think even Valerie knows her plans. At first this was supposed to be a symbolic mission. Visit the moon, return home, show the people space can still be part of our future, but right away things got complicated. The Congress-In-Council tried to block us. Captain Wong was murdered. Every alliance on the planet treated us like threats to their security."

"You are a threat to their security," the sentinel confirmed.

"But why? I don't get it?"

"Your analysis techniques are inadequate," the sentinel observed with a hint of impatience. "Would you have approached a combat mission with such casual gauging of the diplomatic and military ramifications?"

"Maybe you're right," Kris slowly agreed. "Guess maybe I haven't sized up all the players. Until now, anyway."

"A struggle lies ahead, Captain Kris Fairfield," the sentinel grimly warned. "A struggle that will affect humankind for centuries to come. Laureen McKinsey pursues one option, Tranquility pursues another."

"Are you asking me to side against Laureen?" she asked.

"I seek only to answer your question," the sentinel responded. "Come, it's time to return to the landing bay. Colonel Zopek and Doctor Fairfield will arrive soon with your shuttle."

"Glad to hear that. I'm almost out of air," Kris said.

"What!?"

"Yeah, my meter just went O-four. Guess all that extra exertion used up more than my recycler could replenish. Either that or it's damaged."

"Follow! Quickly!" the sentinel ordered.

They climbed back up the stairs, recrossed the bridge, and bounced into the White Towers lobby where a simple code opened the doors of a spacious elevator airlock. Once the doors closed behind them, the elevator began to drop while recallers sucked loose particles off their suits. The chamber filled with a reassuring atmosphere.

"You should have reported the shortage sooner," the sentinel lectured, expediting the life function procedures on yellow alert mode. "Risking environmental malfunction is unwise."

"Guess I forgot to check," she confessed.

"Ridiculous human! Every walker has timers. You must employ your safety features!" the sentinel angrily declared.

"Sorry. Guess we all can't be computers," Kris said.

The sentinel stiffly declined response, remaining silent until the airlock decontamination scanners cleared them for entry.

"Wait here," the sentinel said, stepping cautiously into the foyer.

After heat scanners indicated the area was unoccupied, the sentinel waved Kris on.

The basement staging deck below the White Towers proved to be a group e.v.a. area with dozens of walkers in rotating closets and enough support gear to supply a small army of lunar visitors. Signs posted on the walls provided warnings and instructions for novice moonwalkers.

"After we replace your e.s. unit, we'll descend to the storage level and proceed to the landing bay airlock system," the sentinel said. "You will follow closely, remain silent, and not stop for any reason. If this unit is forced to change course, continue on the designated route."

"Sure, okay," Kris said, concerned because the sentinel was.

The sentinel opened the backpack on her walker and ejected the used e.s. unit, replacing it with a generic substitute. When one of the connections didn't line up properly, the sentinel jury-rigged a feed so quickly that Kris was surprised. For a machine, the sentinel showed a surprising knowledge of procedures necessary only for humans.

"Can I ask why all the fuss'n feathers?" Kris asked.

"Feathers?" the sentinel asked.

"What's got your bug?"

"Identify bug?"

"Whatever is it that worries you? Why all the urgency?"

The sentinel reached into a pouch and pulled out a Remington Four Beam heavy blaster with an activated arming device.

"The Security Computer has initiated red alert function. It may attack without provocation," the sentinel explained.

"That's pretty crazy. Why hasn't it been turned off?" Kris asked.

"Turned off?"

"Yes. Turned off. Deactivated," she said, returning the incredulous glare.

"Captain Fairfield, what good is a security computer that can be arbitrarily deactivated?" the sentinel asked.

"Not much, I guess," she admitted. "But it's not supposed to malfunction, either. Must make a real mess of things."

"Security can be challenging at times," the sentinel seemed to agree. "Now follow closely. Feel authorized to use the sidearm you've been keeping in your tool bag, but only if necessary."

Without looking back, the sentinel bounced slowly through the wide staging area toward a steep ramp labeled SL-1. Kris unlatched the clasp of her tool bag and followed, embarrassed by the weapon she'd thought so cleverly hidden.

____________

Above landing bay major, Valerie and Mike parked New Ranger on the elevator platform and rode down with the shuttle through the multi-chambered airlock system. Anxious to be free of their stuffy walkers, they left the shuttlecraft parked in the receiving hanger and bounced into the ground crew locker room.

"It's great to be free again!" Mike exclaimed, jumping lightly in his padded underwear. "What should we do with these walkers? They're looking pretty beat up."

"We can check them in with the service computer. The automated systems will shake them out for us," Valerie said.

"Don't know if I'd trust a machine doing my shakedown," Mike said. "These systems here are pretty old. What if they screw up?"

"Michael, will you look around you?" Valerie said. "The landing bay is fully active. The tractors work. The life support system functions. We even have clean sheets to sleep on."

"Not that we've been getting much," Mike interjected.

"What I'm trying to explain is that Tranquility is alive. Functioning. This isn't a ghost town like in those terrible horror movies you like to watch. If Laureen is successful, hundreds of people could be living here within a year, and in five years, there could be thousands, just like in the old days."

She finished removing her heavy suit and placed it in a form fitting rack, signaling the service system. The suit rotated away.

"We could sure use a bath," Valerie said.

"My tongue is standing by," he eagerly agreed.

"I was thinking of the hot pool," she replied with a blush.

"I wasn't," Mike smiled.

He grabbed her before she could bounce away, pulled off her bra, then tore off her bottoms as she tried to wiggle free of his grasp, caressing her bare pink flesh as he carried her through the shower room into the spa. The hot pool wasn't up to full temperature yet, but that didn't stop him from throwing her in.

"Michael! This isn't funny. What if someone sees us?" Valerie said, half standing up with her arms crossed over her ample chest.

"We're all adults," he laughed.

"Not that adult. Now help me out!"

When Mike offered his hand, Valerie braced her foot and easily dragged the lunar rookie into the water, giving him the dunking he deserved. After wholesome frolicking under a hot, soapy shower, they moved to the locker room, finding a bench. Valerie kept looking around, wondering where her sister or the others might be. Mike wasn't so cautious, lying down and pulling her on top of him. The wistful gravity made a lot of things possible and Mike tried everyone he could think of.

Afterward, wearing clean jump suits provided by the laundry computer, they started across the hanger toward the hospitality complex.

"It's good that sentinel showed up," Valerie said rather abruptly. Mike's face lost the relaxed smile.

"We could've done it," he said.

"Sure we could. In two or three days. Or next week."

"I thought Kris knew how to work the rigging. She seems to know everything else lately," Mike complained. "Damn defector."

"Defector?"

"To the damn genius society."

"Kris goes her own way, Mike. You know that better than anyone."

"It's not like her. She's been acting strange ever since we got here," he said, shaking his head.

"Haven't we all?" Valerie said. "You and I. Kris. Laureen." Suddenly Valerie felt an eerie premonition. "Please, Michael, let's hurry," she urged.

They raced across the open floor area and up the ramp toward the hospitality complex, but stopped when they heard unusual noises coming from landing bay minor. Crossing through the saloon to landing bay minor, they emerged on a balcony overlooking the emergency exit hatches.

"Look!" Mike called out, pointing at the recessed area below the catwalk.

In the alcove before the locked emergency doors, two oddly shaped electronic units were set upon separate tripod mounts connected by a thick cable.

"What is all that stuff, Mike?" Valerie asked, afraid it might be just what it looked like.

"A molecular disrupter, honey," Mike said, snarling under his breath. "The dish unit is the sender, the box the accelerator."

"Aren't disrupters outlawed? Didn't the Brussels Convention forbid anyone from--"

"Illegal as hell. Someone's got a lot of explaining to do. I turned my head on that permit business, but if Doc thinks I'm standing by for war crimes...?"

Suddenly someone emerged from the alcove dressed in a closed environment assault suit.

"Look. It's Vandebrown." Mike said.

Vandebrown waved to them and hurried up the nearest ramp with rapid, lunging bounces. Despite the heavy equipment, he moved well and with experience.

"Thank God you've returned at last," Vandebrown said, opening his shielded visor. "Where's Captain Fairfield?"

"She chased off after the sentinel," Valerie said. "Please tell me what's wrong? Where's Laureen?"

"I think Doctor McKinsey has suffered a stroke," Vandebrown explained. "I've done my best to make her comfortable."

"Oh God! Where is she?" Valerie cried out.

"In the lodge. First room on the right."

As Valerie rushed down the hall, Vandebrown turned to Mike.

"McKinsey requires better care than we can give her here in the landing bay," Vandebrown said. "I suggest we cut our way out and rush her to the medical center. I've got the drill all prepared."

Mike looked at him, looked down into the bay at the molecular disrupter, then looked back at Vandebrown, not sure what to think.

"What about the sentinel?" Mike asked. "And the security system? Doc said we should sit tight."

"The security system is inoperative. I've tested the relays and response modes," Vandebrown said, his words fast. "As for the sentinel, I think we have the resources to deal with it."

"Yeah, I can see that. Where'd you get the burner?"

"It belongs to Doctor McKinsey. She said it's our insurance policy," Vandebrown said, hoping he was guessing right.

Mike nodded and walked to the edge of the ramp where he could get a better view of the disrupter and the combat gear Vandebrown had laid out.

"Playing pretty rough, aren't you?" Mike asked.

"A disrupter's only dangerous if mishandled," Vandebrown said. "All we need to do is keep the beam under restraint. We'll cut through the emergency exit into the storage bay, then move down to the Loop. Once we deactivate the security computer, we can proceed to the medical center without further trouble."

"You make it sound easy," Mike said.

"Take a closer look. It's all cabled."

Mike bounced down the ramp toward the emergency doors, Vandebrown following at his elbow.

"Are you trying to reopen this base or chop it in half?" Mike asked, pointing at the generator.

"We'll need lots of power to drill through that meteor shielding," Vandebrown said as he pushed the warmup lever.

"Can't we use something less illegal?"

"This hatch is far too heavy for ordinary drilling tools. It would take seven or eight hours," Vandebrown explained.

Mike inspected the coated surface of the emergency doors, poked at the seal, and decided Vandebrown was probably right. Hatches built to withstand meteor impact weren't likely to yield easily.

"What about setting a charge? Maybe we can knock the locking mechanism loose?" Mike asked, not disagreeing so much as probing for alternatives.

"We could, but we could also touch off the airlock oxygen tanks and gut this entire deck."

Vandebrown powered up the accelerator a little more. Mike frowned.

"Yeah, okay," Mike said, pushing the power lever back down. "Just the same, think I'll check on Doc first."

Mike walked back up the ramp toward Kelly's and paused outside the entrance, waiting for Vandebrown to catch up.

"Keep an eye out for Kris," Mike suggested.

Vandebrown nodded and Mike passed through the lobby, entering the first bedroom where McKinsey lay unconscious on the bed. Valerie was kneeling at her side reading a handheld bio-scanner.

"How is she?" Mike asked.

"It looks bad," Valerie said, suppressing a feeling of desperation. "She's been unconscious at least an hour. Her breathing is shallow."

"A stroke?" Mike wanted to know.

"It's possible," Valerie guessed. "The symptoms are present and there's no evidence of injury, but I haven't got the analyzers for a full diagnosis. We must get aid from the medical center immediately."

Mike studied McKinsey's ashen color and reluctantly concurred.

"Okay, get her ready to be moved," he said. "Vandebrown and I will develop our options."

Valerie nodded, struggling to hold back tears.

"Don't blame yourself, sweetie," Mike said, putting a hand on her shoulder. "Doc checked out fine last night. We both know she was faking being hurt."

"I should've been more thorough. I should have stayed with her."

"She's going to be all right. Doc's tougher than you think. Hell, she's tougher than any two of us," Mike encouraged.

He returned to the walkway and found Vandebrown scanning the bay with a heat sensor.

"Any sign of Kris yet?"

"None, Colonel," Vandebrown said, calmly awaiting further instructions.

Mike waved him on and they walked back down to the ground floor of landing bay minor, cautiously scanning the area in case the disrupter had been discovered. Mike looked the equipment over again, shaking his head with disapproval.

"How do you operate this thing?" he finally asked.

Vandebrown smiled a bit too gleefully and handed him a protective helmet with a built-in transmitter.

"Stand here at the modulator control," Vandebrown instructed. "You keep the positive and negative fields balanced. I'll stand behind the focuser and gauge the rate of bombardment. Each time I raise the pulse, you rebalance the feed."

"Sure this thing won't get out of control?" Mike asked. "I've heard stories--"

"This model is perfectly safe," Vandebrown assured.

He reached for the activation switch, closed his visor, and proceeded to power up, a glimmer of blue heat rising from the sender.

"Hey! What're you doing?" Mike asked.

"Cutting a hole in the door, Colonel. Quick! Lower your visor!"

Mike saw the dish emitting pulses that bombarded the heavy ceramic steel doors, the bright flashes and loud whine of the disrupter washing out his senses. He was forced to drop his visor and adjust the colliding fields feeding into the focuser, surprised how quickly the power levels increased. In less than sixty seconds, the first shimmering wave of heat showed where the molecules were beginning to drift apart.

"We are close to zero-two-five!" Vandebrown shouted, expertly holding the field in close proximity. "It won't be long now. Follow my directions or we'll melt the whole base!"

Mike nodded, feedback interfering with his transmitter.

____________

Not very far away, Kris and the sentinel had descended SL-1 and entered the staging level near the garage airlocks. Immediately there was trouble.

Kris didn't see the seeker at first, but was alerted when the sentinel activated a protective series of energy bands. Up ahead, the cause for concern floated on hover jets, blocking their path with forward gunport open. She recognized the seeker as a modified nightwatcher, once a popular patrol unit on Earth until abandoned because of sluggishness. Then it occurred to her that, in the moon's significantly lighter gravity, a nightwatcher would be able to maneuver much faster.

When the sentinel advanced on the seeker, the sphere gave ground, gradually drifting to one side and letting them pass. The sentinel stayed positioned between Kris and the seeker, then dropped back and faced the ominous looking device long enough to make a point. Kris remembered her instructions and moved on slowly, glad to see the seeker break off and disappear up SL-1.

"Some kind of problem?" Kris asked.

"Negative," the sentinel replied.

Kris thought she detected satisfaction in the sentinel's stride as they went down a ramp labeled SL-3 and entered a long, wide warehouse level housing large amounts of spare shuttle parts and service equipment. Tranquility certainly has facilities for repairing shuttlecrafts, she thought, if not actually building a few outright.

Near the end of the storage level, they came to a junction of massive airlocks and emergency doors. Kris realized they were almost back to the landing bays and felt sad the adventure was over. Then, off to her right, she noticed an open hatchway and wondered if there was time for one more exploration.

"What's in there?" she asked.

Before the sentinel replied, she slipped through the hatch and went down a wide circular ramp, emerging on the ground floor of a darkened hanger with the unhappy sentinel on her heels.

"What's this place?" she asked.

"The vehicle storage hanger," the sentinel explained.

"Pretty dark down here."

"Affirmative."

"Why? Doesn't the lighting work?"

"The lighting works fine. This is a classified area."

"Let's not go through that again," Kris laughed. "What's over there?"

She took out her lamp and walked toward a row of storage bays, surprised to find a shuttlecraft parked on a preflight maintenance platform.

"What's this!" Kris exclaimed. "This A-6 looks flight ready? Damn! It is flight ready!"

Before Kris realized what was happening, the sentinel took hold of her elbow and dragged her from the center floor area, not stopping until they reached the comparative safety of a storage bay. When Kris was finally able to regain her balance, she pulled her arm away with a hard shove, knocking the sentinel into the wall.

"What in hell do you think you're doing, Mister? Don't ever put the arm on me again!" she demanded.

"This bay is subject to yellow alert status," the sentinel explained, straightening slowly. "Your presence could be misinterpreted."

"We're being watched?"

The sentinel pointed to the dark upper reaches of the bay. Kris adjusted her scanner and found a hidden heat source. A seeker hovering among the ceiling supports.

"Next time you want my body moved, ask," Kris said, starting back toward the access ramp. Her anger was quickly forgotten.

"Black Raven!" she yelled, seeing the much talked about spacecraft parked in the last bay. "They did make it. The Russians made it."

Kris bounced over to the bay for a closer look. The sentinel reluctantly followed.

"Jeez, look at her. Not a scratch," Kris said. "What happened to her crew?"

"You must return to the landing bay," the sentinel said.

"I want to know what happened to Black Raven's crew. Is it true they're all dead? All four of them?"

"This unit has phrased the request as specified. Please comply," the sentinel repeated.

"But this is important," Kris asked. "For three years everyone's wondered what happened to them. Are they dead?"

"Affirmative," the sentinel said, barely able to answer.

"How did it happen?"

"They disobeyed instructions."

The sentinel turned abruptly and accelerated toward the ramp. Kris ran to keep pace, finding the sudden urgency to flee rather puzzling.

Without comment, the sentinel climbed back up to the storage level, sealed the hatch after Kris passed through, and came to a halt in the airlock junction near the emergency access hatches.

"What makes you think I'm ready to return now?" Kris inquired between gasps for breath.

"You have no option," the sentinel replied.

"Okay, okay, don't get mad. I'll comply with your instructions, but only on certain conditions," Kris offered.

"What are your terms, human?" the sentinel asked.

"Tomorrow I want a complete tour of the base," Kris smiled. "And a tour for the others, too. And I also want answers."

"Tomorrow is too soon. However, your request may be granted in time. This unit does not, however, acknowledge any obligation to offer more than was called for by our original agreement."

"You're a real stickler for rules, aren't you?"

"Affirmative."

"I bet I can make you change your mind," she dared.

"You have nothing I want."

"But you do know about betting? Isn't that rather odd for a computer?"

"Is it?" the sentinel questioned.

Kris sensed a change in attitude, having fun breaking down the sentinel's resolve, when the strangest thought occurred to her, an idea so silly she was embarrassed to consider it. And yet?

Then, just off to their left, the emergency access hatch grew white hot without warning, blistering heat shearing off the door like a furnace. Kris stepped back with a cry of surprise just before an energy pulse surged through, the shock wave knocking her to the floor. Almost at the same instant, the sentinel moved forward with energy bands activated, deflecting the disrupter beam away from where Kris lay. Soon the hatch dissolved into loose particles, the doorway an inferno of twisted metal.

"Prepare to power down!" Vandebrown shouted on the other side, raising his hand to give Mike the cut signal. Suddenly, through the shimmering haze, he saw a humanoid image emerge directly into the pulse! Vandebrown didn't let his surprise prevent him from acting immediately.

"Continue power, Colonel! Continue power!" he shouted at the top of his voice.

"We're close to overload!" Mike shouted back, not daring to look up from the controls. "Hear me? Close to overload. Bring it down!"

"No. No," Vandebrown waved.

"Down," Mike demanded.

"No! More!" Vandebrown yelled, jacking his thumb up.

The sentinel halted in the doorway, protective energy bands turning the radiated force back into the landing bay with great difficulty. Mike hunched against the sudden wave of reversed heat and glanced up, shocked to see the sentinel wavering in the beam.

"More power, Zopek! More!" Vandebrown continued to shout.

Mike shook his head and waved the cut sign, powering down unilaterally. Vandebrown was forced to follow, lowering the temperature of the pulse and gradually cutting back the beam. Within seconds, the landing bay was quiet again except for the spitting sound of molten debris. To Vandebrown's astonishment, the sentinel remained standing in the doorway, the surrounding energy field weakened but intact. Then the sentinel stepped forward.

"God in Heaven, it's still coming!" Vandebrown said in near panic. "Let's see if it can eat this?"

Knowing a laser would be ineffective against the sentinel's energy field, Vandebrown drew an automatic pistol from his equipment bag and took aim, firing five shots in rapid succession. The sentinel staggered backward and collapsed against the door frame, its chest plate buckling under the impact, but before Vandebrown could fire a final shot at point blank range, the sentinel's energy screen flared up and shorted out, the pulse knocking Mike and Vandebrown to the floor.

Vandebrown got up first, his armor having taken the brunt of the force, and looked at the motionless sentinel lying in the melted hatchway, all traces of energy gone. A narrow crack had opened in the chest plate where a sticky gray oil drained slowly on the floor. Vandebrown opened his visor and approached for a closer inspection.

"We did it, Colonel. We did it," Vandebrown boasted.

Getting slowly to his feet, Mike raised his visor and followed Vandebrown to the door, but just as he reached the hatch, he looked through and saw Kris huddled against the opposite wall. He jumped over the fallen sentinel and rushed to her side.

"Kris?" he asked. "Damn it, are you hurt?"

Kris struggled to take a deep breath and tried to stand, but her knees were weak and she went down again.

"For God's sake, Mike, what have you done?" she cried.

Mike looked at the sentinel, saw the gloating expression on Vandebrown's face, and looked at the sentinel again.

"I don't know," he said. "I don't know and I don't like it."

"Look," Vandebrown said, examining the sentinel. "The energy field was so weakened by the disrupter it couldn't deflect my gunfire, but the suit is still intact. This is truly a remarkable outfit. If it breaks down, I might be able to repair it."

When Mike saw Kris nearly in tears, he found himself growing increasingly angry. He had known Kris a long time but only seen her cry once.

"All right, jackal, start explaining!" Mike roared, advancing on Vandebrown with his fists clenched. Vandebrown merely raised the pistol with a sly smile.

"Not so fast, Colonel. I have three shots left," he warned.

"Damn, I knew something was wrong with this. You did something to Doc, too, didn't you?" Mike yelled.

"A simple drug. Harmless now that she has the antidote," Vandebrown admitted. "You jocks really aren't very bright, are you?" He laughed and allowed Mike a closer look at his trophy.

"Is it deactivated?" Mike asked.

"You might say that," Vandebrown snickered. "Though dead is a better word. Wake up, fool. This was a man in a walker. Admittedly a more sophisticated model than I've seen before, but I'm surprised you didn't figure it out." Vandebrown glanced over at Kris for her reaction. She appeared too stunned to follow their conversation.

"A guy? Who?" Mike asked.

"That we may never know for sure," Vandebrown said as he probed the suit for an opening. Next to the sentinel, a scorched side pack spilled open revealing the burnt remains of a medical kit.

Mike took a step forward, but Vandebrown pointed the pistol back in his direction.

"Now, now. Not too close," Vandebrown smiled. "I think I'll require a little more respect from now on. And if you don't want anything to happen to that pretty wife of yours, you'd better..."

Vandebrown's words trailed off as he began to feel dizzy. He wobbled unsteadily, put a hand to his forehead, and found the gun heavy. He looked down and saw a half-burned carton of singed capsules littering the floor. Realization came too late.

"Sedatives," he whispered.

Mike rushed forward and grabbed Vandebrown by the collar, knocked the gun away, and pulled back his fist, but then he, too, felt dizzy. Both men dropped to their knees in a swoon.

Unable to focus her vision, Kris crawled away from the door and tried to sit up, vaguely aware Mike and Vandebrown had stopped yelling. Then, unsure at first, she saw the sentinel move. It was a small shift initially, but gradually the sentinel rolled over, staggered to its feet, and disappeared into the storage level. Kris tried to follow, but her legs were too weak.

An unknown number of minutes later, Kris looked up to see Valerie approaching.

"Val! Stay back!" she called out.

Valerie saw the melted door, smelled the faint trace of a powerful anesthetic, and put on her life support hood before kneeling next to Mike. She was happy to find him breathing normally. The disrupter equipment had been shut down but still emitted heat, as did the smoldering remains of the emergency hatch.

"What happened?" Valerie called out, working her way over to Kris.

"Not sure," Kris answered.

"The tranquilizers have almost dissipated," Valerie said.

Kris knew she was right, already her head was clearing. She stood up and grabbed her equipment bag.

"Take it easy," Valerie warned.

Kris pulled the visor of her walker closed and activated the environmental support unit, then went to pick up Vandebrown's pistol. She turned to the accelerator first, fired three angry shots through the arming mechanism, then stared at the focuser before pulling the trigger. Nothing happened. The gun was out of ammunition. Kris tucked the weapon into her utility belt, kicked the focuser over, and disappeared through the destroyed hatch without a word.

More confused than ever, Valerie pulled Mike against the wall, closed his mask, and boosted the oxygen flow before racing back to the hospitality complex for her medical kit. When she returned a few minutes later, Mike was still propped up against the wall, but Vandebrown was gone.

* * * * * *

Next up: The end of the sentinel