The boat swept low over the top layer of clouds after a fiery entry into atmosphere. Even though there was no hint of dawn in the east, the scene was far from dark. A bright aurora danced across much of the northern sky while lightning lit up the clouds from within. The Earth was also awash with the silver white glow from a full Luna. The effect reminded Sands of Saturn by Archlight.

As they entered into the first of the clouds, Sands tuned into the frequency of the expedition's landing beacon. He was greeted with silence save for the occasional hash of lightning induced static.

"No beacon?" Forbes asked from beside him.

"Nothing." Sands reached out to turn off the radio receiver. His fingers stopped a centimeter from the control as his earphones were filled with a scratchy fragment of speech. The signal was too garbled to determine what had been said, but there was no mistaking the human voice that had spoken the short, sharp command. He waited for long seconds, but there was nothing more.

"What was that?" Forbes asked.

"A call for help? The raiders?"

"Call up a bearing and see where it came from."

Sands keyed to have the source of the signal plotted on the navigational display. As he had suspected, the signal source lay on a direct bearing to the energy screen laboratory."

"Was that the Alliance?" Spacer McCarver asked from the landing boat's right rear seat.

Sands grunted his agreement. "We're still well below their horizon. We must have picked up a ground reflection."

"Do you suppose they were talking to their ship?" Forbes mused.

"Does that worry you?"

"Damned right it does! If they're above the horizon, they probably saw our ion wake as we reentered."

"Maybe the ship is on the ground," James McCarver said.

Sands considered the possibility. If McCarver were right, it would alter the tactical situation considerably.

A ship on the ground might be put out of commission by high explosive slugs if a marksman could get close enough without being seen.

Sands glanced at the course readout. They were flying northeast, aiming at a point several hundredkilometers north of the laboratory. They planned to fly eastward until they were behind the coastal mountain range, then turn south and use the mountains to shield them from any Alliance sensors that might be watching the sky. Since they were moving slantwise with respect to the direct line to the laboratory, it would be possible to triangulate the position of any additional signal. With luck, they might be led to a grounded Alliance spaceship.

The next signal was gone almost as soon as they detected it. Despite this, Sands carefully recorded the bearing and added it to the moving map. The new bearing intersected the first at the energy screen laboratory. Over the next five minutes, he detected three more signals. All originated at the laboratory site.

While Sands worked to locate the enemy, the landing boat dropped through the clouds and into clear air.

By the light of an occasional lightning flash, Sands made out the ancient sea bottom. Then they were at the long, irregular line of the coast and headed eastward toward the tall mountains. They crossed the mountains, and then dropped down low as they swung south. The boat flew for some fifteen minutes before they drew abreast of the laboratory. Forbes turned west and sought out a pass through the mountains.

"Nothing," Sands growled as the mountains cut off any hope of intercepting further signals. "And there's no sign of a second source."

"Maybe the ship is aground at the laboratory and we're picking up chatter between them and the ground party," McCarver suggested.

"We'll know soon enough," Forbes muttered as he concentrated on his nap-of-the-earth flying.

The eastern sky had gradually brightened all through the trip south. The landscape had taken on a dead gray color as dawn seeped through the clouds. The morning light revealed the rugged beauty of the mountain range as they streaked between peaks at nearly a thousand kilometers per hour. They hugged the floor of a valley that had once been cut by a small stream. It reminded Sands of dodging in and out of the clouds back home.

They came out of the mountain pass and skimmed low over rolling foothills. Then Forbes pulled the nose up and fired the underjets. All three of them went "Oof!" as deceleration dragged them down into their seats.

The landing boat dropped like a stone. Sands felt his sphincter muscles automatically clamp down as the ground rushed up below them. The underjets fired again just before they hit. The boat grounded in a cloud of dust, bounced once, and then was still. Sands was conscious that he had been holding his breath. He inhaled sharply and began undoing his restraining straps.

He climbed out of his seat and clambered quickly to the rear of the wing. The steely gray light was stronger than ever as his boots touched the powder dry earth. He looked around. Before him was a tall hill. Beyond it lay the energy screen laboratory.

He and James McCarver loaded their packs and set out on foot. Behind them, Forbes fired the boat's landing jets and brought it to a hover. Once in the air, he moved close to a vertical cliff face where it would be less conspicuous. It had been agreed that the pilot would remain with the boat and wait for their call.

It took nearly half an hour to gain the top of the ridge. They arrived puffing and out of breath. Theycrawled the last hundred meters on their bellies to ensure that they would not be silhouetted against the clouds. By the time Sands reached a vantage point from which he could see the laboratory site, his suit was covered with a fine coating of dust that caused him to blend into the surrounding landscape.

Lying prone in an environment suit is a good way to develop a stiff neck, Lars discovered. He ignored the discomfort as he levered himself up on his elbows and brought a pair of binoculars to his faceplate.

Their perch allowed them to look down on the energy screen laboratory some three kilometers distant.

The first thing Sands noticed was that the communications tower had been toppled. That had undoubtedly been the cause of Kimber's signal being cut off.

He turned his attention to the small cluster of machines that marked the +entrance ramp. He watched for nearly ten minutes without seeing any movement. He then scanned the hill, searching for any sign that would indicate the raiders were still occupying the laboratory. He found nothing. At the end of his survey, he signaled McCarver to hook up a hard commline. The young spacer reached out and plugged a cable into the base of Sands's helmet.

"See anything?"

"Nothing."

"Maybe they've gone."

"And maybe they are lying in wait for us. I wish I could see into the roadway leading to the main entrance."

"What do you want to do?"

Sands hesitated. It would take at least forty minutes to reach the laboratory site via the direct route, and possibly twice that long if they were to avoid being seen. He considered his options and decided to play it safe.

"We work our way down that valley to the hill, then up that ravine on the south until we reach the comm station at the summit.

"And once we get there?"

"We can get in through the utility tunnel. Chances are they haven't discovered it yet."

"Good enough for me," McCarver said. "Let's get started."

As they trekked across the dead landscape, Lars was thankful for the long days he had spent toughening his muscles. His newfound physical condition allowed him to set a pace the younger man was hard pressed to match. They made it to the base of the hill in just under an hour. As they started up, Sands could not shake the feeling that a dozen pairs of eyes were watching his every move.

It took another twenty minutes to reach the ruined communications gear. Once again, they slithered the last hundred meters on their bellies. From up close it was obvious that the comm station had been demolished by a bomb. Once again, Sands signaled for a hard line conference.

"You stay here. I am going to reconnoiter the utility tunnel. If I'm not back in an hour, get back to the boat."

"I should cover you."Sands shook his head violently inside his helmet. "No! Someone has to report back. You stay here.

That's an order!"

"Yes, sir."

Lars unplugged from McCarver, then worked his way toward where they had found the buried Borman cable. At the end of it, he came to the manhole through which they had first entered the underground facility. He pried the cover off, moving with care to make a minimum of noise that might carry underground. He dropped awkwardly through the hole and levered the cover back into place. The tunnel was dark. He switched on his helmet lamp and was momentarily dazzled by the beam.

He began crawling in the direction of the laboratory. It was nearly five hundred meters from the manhole cover to the cable room where the utility tunnel ended. Every muscle in his body ached before he had covered half the distance. Sweat poured down his face such that he had to stop every few seconds and wipe his forehead on the wiper pad built into the helmet. As a result, he did not notice the body sprawled face down in the tunnel until his gauntletted hand touched someone's leg.

Lars's heart stuck in his throat as he got on his knees and flipped the body over. It was Paolo Renzi.

The scientist at first appeared to be dead. Lars let his helmet light wash over Renzi's face and was rewarded by a slight twitching of eyelids. Renzi's mouth moved and Sands's receptors picked up a croaking sound. It was a moment before he realized the scientist was asking for water. Lars detached the spare water reservoir from his suit's backpack and awkwardly held it to Renzi's lips.

Renzi gulped instinctively. Sands glanced at his external temperature indicator. The air inside the utility tunnel was at 65C, uncomfortably warm, but far below the killing 150C outside. Obviously, air-conditioned air from the laboratory was seeping into the utility tunnel, moderating the effect of the hot rock around them.

Sands switched in his helmet speaker and chinned the control for minimum volume. "Wake up, Professor!"

Renzi's eyes flickered open and he recoiled from the sight of the armored figure leaning over him.

"It's Larson Sands, Professor. You are safe. Do you understand me?"

Renzi's eyes seemed to focus. "Sands?"

"That's right, Professor. What happened here?"

"The Alliance," Renzi replied in a hoarse whisper. "Everyone was in the vault looking over the data. I had returned to my quarters to pick up some notes. That was when they blasted the front entrance. The others were trapped while I hid behind a set of filing cabinets. Then while they were busy elsewhere, I made my way here."

"Where are the others, Professor?" Sands asked so softly that he wondered if Renzi had heard him. He was about to repeat the question when the scientist stirred once more.

"They're dead, I think. There was shooting, then an explosion."

The strain of those few words proved too much for him. Renzi lapsed into unconsciousness. Lars set his jaw and carefully lowered the professor to the tunnel floor. Then he crawled the final few meters towhere the utility tunnel entered the laboratory. He noted that the access panel had been torn loose, then hurriedly propped back into place. A gap of several centimeters allowed the laboratory air to mix with that in the tunnel. He switched off his light before carefully moving the panel out of the way. He then squirmed into the main laboratory complex.

The main tunnel was alight with the widely spaced emergency lamps they had installed shortly after excavating the entrance ramp. One glance at the outside temperature indicator told him that the environmental system was no longer working. The laboratory was heating up minute by minute. Sands got to his feet and slowly worked his way toward the vault. He stepped cautiously, sweeping his riot gun from side to side slowly as he walked.

At first, he searched with great care lest he stumble upon the enemy. As it became evident that the raiders had gone, Sands stepped up the pace. He reached the vault door and found scorch marks around the hole they had cut. Stepping through, he found the inside of the vault a burned out hulk.

The source of the destruction was obvious. Explosives had been carefully placed in the heart of the massive apparatus inside and then set off. Following the blast there had been a brief, violent fire that had burned until all of the oxygen had been consumed.

As Sands walked through the ashes, he braced himself for what he knew he would find. There, near the far end of the vault, was a pile of bodies. The fire, which had undoubtedly been intended to consume them fully, had gone out too quickly. Although scorched, Sands could make out enough details to identify the dead.

He recognized Arthur Linder first. The geologist had been shot in the forehead and lay sprawled on his back. Park Eald and Taren LeBlanc were lying side by side. All showed evidence of having been shot.

As Sands continued the grisly task, his tension rose until it was nearly unbearable. Each moment he expected to discover Kimber's body. Yet, when he was through, he had found no sign of Kimber or Halley. Even though some of the bodies were damaged badly enough to make identification difficult, one thing was clear: All were male.

Sands was overcome with the same rage he had felt at seeing his brother shot down aboardDelphi .

With his rage came fear. The absence of Kimber and Halley among the dead in the vault made him think of rape. He searched the full vault before heading for the living quarters. His heart was a drum pounding in his temples as he hurried through the chambers they had used for sleeping. There was no one to be found.

His next stop was the communications room. The equipment had all been smashed by a blunt instrument.

The cables that fed signals to the comm station at the top of the hill were still intact. Sands pulling the commlink line from his belt, touched it to the bare end of an antenna cable, and said, "McCarver?"

"Here, Mr. Drake," came the reassuring answer.

"We've got a lot of casualties down here, but no bad guys. I think they must have lifted off while we were behind the mountains. That would explain all the chatter we picked up during our approach. Come in through the utility tunnel. You will find Professor Renzi near the exit. He is in bad shape. Stay with him."

"Yes, sir."

Feeling emotionally drained, Sands retraced his steps. He searched the laboratory again. This time he searched meticulously, checking every possible hiding place to make sure no one else had escaped and then been overcome by the heat. It took him nearly half an hour to finish the grim exploration. He foundnothing save smashed equipment and ransacked record cabinets. The raiders had removed every record tile in the place.

A great exhaustion overcame Sands as he made his way back to the utility tunnel. He found McCarver cradling Renzi in his lap.

"How is he?"

McCarver glanced up. "Better. I have been pouring water down him. He was awfully dehydrated. How are we going to get him out of here?"

"There are still environment suits near the entrance. They've been pretty well worked over, but we should be able to cobble together one that will get him to the ship."

"What about the others?"

Sands described what he had found in the vault. The young spacer's features grew grim in the gloom of his helmet. Sands finished by telling him his suspicions that Kimber and Halley had been taken to the raiders' ship.

"What do we do now?"

"We get Renzi back to our own ship. Come on. You grab his legs and I'll take his arms." They carried the unconscious scientist into the main tunnel where it was cooler. He woke as they lay him on the floor.

"The energy screen data!" he croaked.

"I'm sorry, Professor, but they got it."

"We must have it back."

"Not much chance of that. They blew the vault. It is so much scrap metal. They've destroyed just about everything."

The scientist gripped Sands's gauntletted arm and tried to pull himself erect. Sands gently pressed him back. "You rest. James and I will get you a suit."

"You don't understand," came the urgent gasp. "We've got to get that information back! The ancients didn't know enough..." With that, he collapsed again. Sands watched him gasping for breath in the pool of light made from his and McCarver's helmet lamps. When Renzi spoke again, each word was an obvious struggle.

"We were reviewing the energy screen data when I realized that I recognized the derivation of one of the space tensors. The ancients limited themselves to a special case because they knew nothing of hypersets!

They could never have built a planet size energy screen with what they knew."

"Take it easy, Professor," McCarver said. "You can tell us the rest when we get you up to the ship."

"No, I must speak now. Don't you understand? I recognized their mistake! We have learned a great deal in the past two centuries. We can succeed where they failed. Wecan build an energy screen capable of cooling the Earth!"

Chapter 27: Prisoners and Pursuers.