Hanovich gestured to one of the men behind a control panel. The man touched the panel in front of him and the image of the room and the woman in it slowly revolved. Her appearance was quite as spectacular when viewed from other points as from the front.

Beautiful, and she knows it, Larry thought. The perfection of a statue, with a personality to match. Aloud he asked, 'That's a pretty spectacular effect but are you certain they've done nothing?'

Hanovich was too distracted to hear. Larry had to repeat himself before he got an answer. It was from one of the other men in the room.

'They had an appointment to tour the crater by transporter at 1700,' he said. 'We canceled it.'

Now the view moved back, up at an angle and away from the woman. The image shrank until they were looking down on the whole suite, floating in midair above the stage. The people inside moved around like little living figurines in a dolls house with almost transparent walls. Larry could even see inside the closets, and through the bottom underneath the beds.

'All right,' Larry said, after considering the matter a few minutes, 'a.s.sume they're a diversion.

Has anything happened that you might have covered instead of these people?'

'No,' Hanovich answered. 'They arrived at Customs in an airtight ambulance transporter. They didn't have any vacuum gear nor was there any along their trail back to the loading dock. Customs is at the entrance to Copernicus instead of at the loading dock because there's nowhere else out there for anyone to go ... oh . .. THE WORK PARTY!'

Hanovich looked around the room for an instant to see who was there and who might have overheard and condemn his oversight. Then, realizing that it was too late for that, he hurried from the room. Larry followed him.

The men remaining in the room watched the suite in silence. Brooding like giant G.o.ds over a little transparent cage containing human beings.

CHAPTER TEN.

WHERE THERE'S SMOKE THERE'S ...

4142

The alien entered Copernicus from the west entrance in a transporter with a group of the other members of the work party. With him he brought a bag of things that would never have cleared Customs, if there had been any at that entrance. The transporter stopped at the Dome, and he got out. His first stop was at a public telephone where he made a collect call to Tellus. When he had verified that he was connected, he attached a multi-frequency receiver over the mouthpiece and put up a sign reading, 'Do Not Disturb. Equipment Being Tested.'

From there he went to a public restroom. When he left the restroom he bore a striking resemblance to one of the men in Maintenance. Those seeing him might have mistaken him for the other man except for a wrongness: A clumsiness a.s.sociated with a man coming from a larger planet moving in the lesser gravity of a smaller one. A clumsiness that marks newcomers and tourists. But then, no one notices tourists, and newcomers are ignored.

The alien went by travel tunnel to a remote area. He paused for a moment at a doorway in the travel tunnel marked Authorized Personnel Only. An entrance to part of the maintenance facilities.

Bracing himself with the handle beside the door, he inserted an automatic lock pick in the lock, opened it and went inside. The television camera watching the door from the inside only caught a glimpse of him as he pa.s.sed.

At the other end of the circuit, in a secure area of the Maintenance Building, the monitor was caught by surprise. 'Was that Perdue?' he asked his partner. 'I didn't think he was working this shift.'

'No, he's not on,' the second monitor answered. 'Where did you see him?'

The first monitor indicated the proper plate.

'Let's alert Security that we may have an intruder, and let them check it out. It might be a false alarm but let's make sure.'

'I'll connect a video recorder to that plate.'

'Good idea.'

The alien went through another door into the ventilation system. It was a large, metal-sheathed room with rotating screens covering one intake wall and a large hole in the floor near the opposite wall. He went down the hand grips into the hole, which was the entrance to a very slowly turning, elbow-shaped pipe. The air left the travel tunnel's inertialess field here and flowed into the concrete and reinforced steel room that surrounded the pipe. The edge of the inertialess field was indicated by a red, glowing marker field that stretched in a parabola from the mouth of the pipe back almost to where he was. The portion of the outside wall that he could see was pockmarked with holes caused by small particles not sifted out by the rotating screens, that escaped the parabolic-shaped field. Around the edge of the field he could see a faint cloud of material entrapped and waiting. It was expending its intrinsic energy against the flow of air moving past it.

The alien looked around and found an irregularity in the surface of the pipe. He hooked his feet in the hand grips and, using his fingernails, peeled up a large, metallic-colored plastic patch.

It was the side of a bag containing welding equipment, magnets and many large, colored, plastic tubes of sand.

He attached the bag to his belt, opposite the other bag, and retraced his path back to the travel tunnel, past the television camera.

'By G.o.d! That isn't Perdue! Call Security! Tell them we need patrols to check out that ventilator area and to catch that guy. I'll try to keep him in sight with the tunnel cameras.'.

As a result of Rog Philips' a.n.a.lysis of critical points, as much of the travel tunnel system as possible was being continually watched. Holes had been pierced in the ends of each tunnel for television cameras with light-field lenses. A camera focused on the alien as he left the maintenance area. Although it was thousands of yards away, the image the monitor saw was sharp, and filled the screen. It blurred only slightly as people pa.s.sed between the camera and the object. The monitor followed him along the travel tunnel. Another camera picked him up as he came out of an intersection, having shifted from an east-west tunnel to a north-south one. He traveled north. The camera at that end of that tunnel picked him up and followed him right up to its end, where he took an object out of his bag and stuck it to the end wall, out of sight of the camera.

Then he turned and hurried away.

'Where's that second patrol?' the second monitor bellowed. 'Tell them he's put something on the north-end wall of Tunnel A.'

'They just turned the corner at A-Zero. They'll be there in about two minutes.'

'They better move faster than ... My G.o.d!'

'What happened to the camera?' the first monitor asked as the plate showing the alien turned black. He zoomed up the camera from he other end of the tunnel, that he had been using to watch the patrol's progress. 'Smoke! That was a smoke bomb! Tell security to get IR goggles to the 4243

patrol.'

Security didn't have to be told. They were literally watching over the monitor's shoulder through a video relay.

Col. Hanovich and Lt. McQueen were in Security's control center with one of the dispatchers. They had called the work party and discovered that two men fitting their requirements had joined the work party outside the entrance to Copernicus, and that at least one of the men was now inside Copernicus. They had men interviewing members of the work party. They missed the first intruder alert by the monitors because of a bar room fight involving a couple of members of the work party who were celebrating their pay day. When the intruder was definitely identified as such, the dispatcher handling the situation immediately switched the problem over to their dispatcher.

'That establishes his ident.i.ty,' Hanovich said, when the smoke bomb went off.

'Yes,' Larry agreed. 'I doubt if Customs is in the habit of letting something like that in.'

'How far will the smoke spread?' Hanovich asked the dispatcher.

'To the nearest air vents.'

'What's in that area?'

In answer this time the dispatcher called up a map of the area on his auxiliary plate. It showed the system of travel tunnels. North-south tunnels were lettered A through J.

East-west tunnels were numbered from 2 North through Zero, which went through the Dome, to 2 South. While Hanovich and McQueen examined the map, he sent in additional patrols with infrared goggles.

'There's nothing connected to that area of tunnel except a bunch of tourist-crater view apartments,' Hanovich commented. 'No main air, only one main power line, no water, no fuel supply, and it's too far from our communications or defenses.'

'Right,' Larry agreed. 'So it's got to be an attack on either the wall to the outside or the travel tunnel Bergenholm.'

The first patrol reported finding nothing in the air vent the alien had left.

There was a long pause as the dispatcher looked inquiringly at Hanovich. Finally he asked, 'What do you want to do now?'

For a few moments it seemed to McQueen that Hanovich had gone into a trance. He stood there blankly, unmoving, scarcely breathing. Larry was about to make a suggestion when Hanovich woke up and took hold.

'Evacuate the travel tunnel system and close off the entrances so no one will get into them except us. Notify Judge Fox that we're firing up the big spy-ray with or without a warrant. Start organizing patrols. We'll need at least 10 two man teams. How many do we have down there and ...'

He gave the dispatcher a worried look. 'Does anyone down there have armor on?'

The smoke followed the air currents, expanding to fill the northeast corner of the travel tunnel system. The alien escaped the smoke by going up an exit shaft about 20 feet. Fresh air from the doorways above was drawn down into the shaft keeping it clear. Even if it hadn't been clear the alien's special goggles would have permitted him to see through the smoke.

He inspected the wall and found a scratch scribed in the slick coated surface. He fastened himself to the metal underneath the plastic-coated surface with magnets, and checked his wrist watch.

Based on the time he selected a point on the line, started the torch, put on he welding helmet with its built-in respirator and began cutting a hole around the point in the wall. Hot vapor and small particles from the heated metal drifted off toward the ventilation exhausts. Within two minutes enough had acc.u.mulated in the nearest parabolic outlet field that new alarms were ringing.

If the monitors were worried before, this made them panic.

As the alien cut out the circle, the light material bent back toward the edge of the travel tunnel's inertial field. He had just about finished cutting when a minute sliver of the edge of the circle pa.s.sed outside and regained its original intrinsic velocity. It PULLED, jerking the entire disk out of the field almost instantly! A volcano of hot material erupted up out of the hole as it penetrated the concrete outer liner of the tunnel and the solid rock behind the liner, at a speed measured in miles per second!

The alien jerked back out of the way! The incandescent geyser slowly dissipated into the travel tunnel shaft. He turned off the torch and put it away. While waiting for the air to clear, he sorted out all the tubes of the same color in the bag.

When the air was relatively clear again, the alien had loaded a dispenser and began carefully releasing a small stream of finely divided sand from the tube into the hole. It disappeared into the outer wall of the travel tunnel but in a new direction. There was a big flash and a spray of material as each little particle of sand punched the hole deeper and deeper into the rock. When the material stopped erupting back out of the hole, he knew that he had penetrated into the area 4344

around the Bergenholm vault, a hundred feet or so away.

The alien hesitated a moment before proceeding to the final step in his attack. He didn't know how many of the three Bergenholms were operating but it was obvious by the continued existence of Copernicus that at least one of the power line-actuated, explosive charges had not gone off. If this was the one carrying the whole system, all of Copernicus would be instantly converted into an ebullient inferno. He braced himself to die and started releasing whole tubes of sand.

The outer screen of the Bergenholm vault was penetrated by the fifth tube. It blinked out of existence, leaving the vault wall and the internal screen behind it accessible to attack. The internal screen was somewhat stronger than the outer but it was struck not only by the inert tubes but by intense jets of plasma generated by the tubes sc.r.a.ping the edge of the hole into the vault chamber and large chunks of the outer vault wall riven out by the impacts. The screen collapsed after another two tubes. .h.i.t it. The alien continued releasing tubes until all of those of the same color were gone.

It was with mixed emotions that he put the welding helmet away. Relief at still being alive; disappointment that his mission was not complete. He donned goggles, removed the magnets, drew his gun and went back down the shaft into the smoke of the tunnel below.

The impact of each tube was felt all over Copernicus. The travel tunnels had been vacated by everyone except Security. All of the entrances were closed. Anyone could have entered through an exit but the closed entrances and the sound of the attack on the vault warned residents that something unpleasant was going on inside.

Col. Hanovich and Lt. McQueen had been watching the vault on the alternate plate when the shields collapsed. 'How?' Hanovich asked, incredulous, 'how is he doing it? What is he using?'

'Something three, maybe four months old, that was stored in the ventilator,' Larry answered. 'In that time it would have an inert velocity of about 100,000 feet per second. That would give a two- pound object about 10 million BTU's of energy. As much as four times that if it's been there six months. But that doesn't answer the real question. How do we get him?'

'I don't know,' Hanovich answered, and shrugged. 'Wait until he runs out of smoke and gives up?'

'Figure he'll come walking out with his hands up?'

'No. Not really - but what else can we do right now?'

'I don't know,' Larry smiled sadly and shook his head. 'I can't see any other way either.'

'The spy-ray team is certain that the block is moving,' the dispatcher interrupted.

'Alert the security patrols that ...' Hanovich started to say, then hesitated as the next series of events unfolded on the plate overlooking the monitor's cameras.

The alien had proceeded westward in tunnel 2 North, and hidden in the smoke on the other side of the ventilator from the four men guarding the tunnel there. He waited for a clear shot at all four. Then he rayed them down, almost before they realized what was happening. Reaching up, the alien hooked a handle and used it as a pushing off place to launch himself and go flying down the tunnel past the injured and dying men.

For an instant his free flight was many times faster than the transportation system of handles.

Then he brushed a wall, went into a flat spin and caromed off the walls of the tunnel. He wound up against one of the pedestrian stops used by travelers when getting off the handles. After that one experience, he traveled more sedately, using the handles.

'He's wearing goggles,' Hanovich said accusingly as he watched the intruder flee down the tunnel.

'Why can he see when our people can't?'

'It's his smoke,' Larry answered. 'He can have a window in it wherever he wants. It's probably tailored to his goggles and not to our general purpose ones. He's also suicidal.'

'What do you mean?'

'He hasn't left the travel tunnel system for at least 15 minutes now. That means that when he comes out he'll have a high intrinsic velocity. When he came out of the smoke he wasn't using a respirator either. That means that when he comes out of the tunnels, the particles of material he breathed when he cut into the travel tunnel liner will tear his lungs out. He either doesn't know, or doesn't care what happens to himself, as long as he succeeds in destroying the travel tunnel Bergenholms. No casual effort is going to stop him. Let's reorganize the center and concentrate all our efforts on him.'

'How?'

'a.s.sign two dispatchers to handle the security patrols only and have the other two dispatchers handle whatever special tasks we or anyone else can think up.'

Hanovich agreed. It took a couple of seconds to arrange.

'Now, two tasks,' Larry continued. 'Bill, find Out if the spy-ray team can correlate the intruder's visual location with the edge of his spy-ray block. And Ira, find out if Rog Philips 4445

has one or two of the remaining Bergenholms working. If the western one is the only one, tell him to get the other one on line fast!

'Can you get this patrol here,' Hanovich said to another dispatcher, pointing to the map on his plate, 'to intercept over here in time?'

'I can try,' the dispatcher answered, and started issuing the appropriate directions.

'Are the medics on the way to our men yet?' Hanovich asked the last dispatcher. He received an affirmative reply. 'OK, try to bottle the intruder in the north-west corner.'

A few minutes later answers started coming back. The spy- ray team couldn't pinpoint the intruder because his block was odd-shaped, and b.u.mped around in a random manner as he moved, but they could tell when he moved more than a few yards. Rog Philips answered that the intruder was now heading for the only Bergenholm in operation. Maintenance had been checking the third one and it would be at least 30 minutes before they could have it put back together. Larry interrupted Ira and emphasized that they hurry, otherwise they might not live long enough to get it together. He also asked Rog to keep in constant contact with the Security Control Center.

A patrol dressed in armor just missed the intruder at the intersection of tunnel H and 2 North, and gave chase. The intruder threw a live smoke grenade ahead of himself toward the end of the pa.s.sageway, and used the fumes trailing from it for cover. When he got to the last intersection in the corner, he threw another grenade through it into tunnel J. Then he proceeded cautiously inside the smoke cloud into tunnel J and southward. It would take him a little time to get into position to destroy the second Bergenholm but now he felt he had all the time he needed.

'The spy-ray team say he's transferred into tunnel J,' the dispatcher reported.

'Any ideas on how we stop him?' Larry asked Hanovich.

'Have the patrols fire blindly into the smoke?'