GOVERNOR Chanto Grieg signed the waiver and pushed it across his desk toward Fredda Leving. She reached for it a bit too eagerly, and that bothered Grieg. There was something wrong here. Grieg pulled back the paper and held on to it.

"I do not understand why you are demanding this bit of paper, Fredda," Grieg said. "I'm still tempted to refuse it and take my chances on your threat to resign from Limbo."

"Please, Governor, give me the waiver. I assure you that I am not bluffing. If you refuse it, I will resign. I will wash my hands of the whole matter."

But Grieg still held on to it. "You realize this waiver is not retroactive," he said. "It does not absolve you from the crime of building a Lawless robot. It merely notes that you take responsibility for exactly one such robot as of today and are granted permission to own it. You could still be brought up on charges, very serious charges. If Kresh decides to arrest you, there would be nothing I could do. This piece of paper will do nothing to protect you."

"It is not me that I am looking to protect," Fredda said. "I have done almost nothing except think about this question since the riot. At first, I wanted to go and hunt him down myself. I wasn't sure if I wanted to find him to save him or to destroy him. But the more I thought, the more I knew I did not like the idea of his being captured and executed for the crime of being the way I made him. If he dies, it will be because I committed the crime of creating him. He should not be punished for my crimes, but that will be what happens to him without this waiver."

"In my opinion, the preponderance of information still indicates that he committed the attack against you. The situation is confused, but that still seems the most likely explanation."

"Then if that is shown to be true, let him be punished for what hedid. That would be justice. To destroy him for what heis would be savagery. Caliban is the first robot with no shackles on his intellect. He is the first with the potential tothink the way we do, except that perhaps he will do it better. He is the first robot made for freedom. And for this crime, he is to be hunted down and destroyed. I say that if we are so threatened by the freedom of others that we must kill them, we are not deserving of freedom ourselves-and we will not keep it long."

Governor Chanto Grieg did not speak, did not look at Fredda Leving. Instead he turned to the magnificent city that was slowly decaying outside his window. "That's a big change you're talking about, Dr. Leving, and change is never easy," he said. "Sometimes I feel as if I am a doctor with a very sick patient, and the only medicine I have is change. If I administer too much of it, or give it at the wrong time, it will kill the patient. But if I instead prescribe no change at all, the patient will surely die. More than once, I have wondered if we Spacers will ultimately decide that change is too bitter a pill. We may decide that it would be easier, more pleasant, to refuse our medicine and to die instead. What do you think?"

"For the moment, sir, that waiver is all I am interested in. May I have it, please?"

Grieg looked at Fredda, her eyes bloodshot and sunken, her face pale, a bit of the scruffy stubble of her new-growing hair peeking out from under her turban. This was a woman long past worrying what she looked like, a woman who had clearly been struggling for some time with the question of what was the right thing to do.

At last he spoke. "Very well. If our society is so fragile, so rigid, that it cannot survive the existence of a single No Law robot, then I doubt very much if there is much chance of keeping the patient alive in any event." Chanto Grieg handed over the slipof paper.

"Thank you, sir. Now, if you'll forgive me, I must go." Fredda bowed, turned, and left.

Chanto Grieg watched her as she left, and found himself alone with the very uncomfortable notion that he was not at all sure Infernocould survive the advent of a single free robot.

In which case, of course, there was no hope at all.

THERE was no more point in further static practice. Either the thing would work or it would not. Either he could pilot it or he could not. Caliban sat in the pilot's seat of the open cockpit aircar. He gripped the controls firmly, adjusted his feet over the pedals, and engaged what he thought was the lift control. The car lifted slowly off the ground. Yes, good. It worked.

He had been more worried over whether the car wouldwork than whether he had figured out the controls properly. After all, it seemed likely that the car had been sitting, forgotten, in Periphery Skyport Six since the underground Skyport went out of service, sometime in the last century. Working by his internal infrared light source, Caliban brought the decrepit old craft up to a reasonably steady hover at about ten meters over the floor of the cavernous room. He performed a circuit of the room with about as much grace and agility as one of the more elderly citizens he had seen tottering about the city his first day out on the street.

Yes, throttle, lift, directional controls-he had divined them all properly. Aircar operation was yet another area where his datastore was frustratingly silent. He had been forced to work it all out for himself, and he was acutely aware that there was a great deal he did not know about how the aircar would handle in anything besides low speeds and still air.

But now, assuming the aircar held together, there was little purpose in further delay. It was time to set out. Caliban eased the car gently into the wide egress tunnel and guided it at a sedate ten kilometers an hour, moving in illumination provided by his infrared system, following the gentle upward grade of the tunnel as it moved toward the surface. The moldering walls of the tunnel drifted past in silence. Even after all his explorations of the underground world, this wide, broad tunnel into the darkness, the whole Skyport complex, was still cloaked in strangeness.

The place had a feeling of age, of years passing while it sat here in silence-and yet there was also the sense that this place had never been used. Everything was old, but nothing looked even slightly worn. It was all new under the dust.

It took a minute or two to reach the long-sealed exterior door. He had walked up the tunnel and examined the mechanism earlier. He was reasonably confident that he could open it, but that was nothing he could count on. Even getting it opened would not solve all his problems. It seemed at least possible that the Sheriff's Department would be watching the tunnel entrances around the periphery of the city. That was why he had not opened it before now: no sense advertising his location until he was ready to leave.

Assuming he did get the door open, he would have to move fast once he was through. That was the reason for choosing an aircar rather than attempting to get out on foot.

And he would have to leave soon. In another day or so, his power supply would reach dangerously low levels. He dared not search for a recharging station inside the city. The deputies were everywhere in the tunnels, and he had had several narrow escapes already. He did not wish to be forced to stay in one place for the hour or so a recharge would take. Besides, it would be the height of madness to so much as approach a recharging station. He had to assume Sheriff Kresh would have the sense to post guards over all the recharge stations. No. He had to get out of the city and find a power source out there. Somehow.

There was the end of the tunnel. Caliban landed the aircar with a bit more of a bump than he intended and got out. He walked over to the door controls and flipped the switches for the manual control.

With a thump and a hum and thechuff of the overlying dirt and dust dropping into the tunnel, the door opened.

Before the door was even fully retracted, Caliban was back in the pilot' s seat. He threaded the ancient aircar through the entrance and then cranked the lift control and forward thrust to maximum, seeking to put as much sky and distance as possible between himself and the city of Hades.

BY now, Alvar Kresh was thoroughly used to having his sleep interrupted. This time when Donald touched him on the arm, he came fully awake at once, with no intermediate stage of confusion. He sat up, swung his feet around onto the floor, and stood. He crossed to the chair where he had laid out his clothes upon going to bed. If he was going to dress himself, he had no intention of losing any more valuable time fumbling for clothes.

"What's the report?" he asked.

"It could be nothing, sir, but it seems at least possible that it is Caliban. The robots working the city status monitors were instructed to report anything unusual. They are a rather conservative design and they reported all sorts of routine events, making it difficult for their human supervisors to distinguish the truly unusual-"

"Damn it, Donald, get to it!"

"Yes, of course. Forgive me, sir. One of the peripheral skyports opened its external hatch for the first time in fifty years."

"Thatqualifies as unusual."

"Yes, sir. In addition, city traffic control reported an aircar lifting off from the position almost immediately thereafter, flying faster and higher than allowed for by ordinance, but accelerating to that speed rather slowly."

"As if the pilot wasn't totally confident of himself or his craft. Yes. What's the intercept situation?" Kresh stripped out of his pajamas and started to get into his clothes, this time remembering that life was easier if he got the blouse on before the pants.

"Two of our aircars are on the way, but the craft they are pursuing is now at speed with a fair lead. He is heading due north, toward the mountains, flying straight into a rather heavy storm. And I need hardly add a nighttime pursuit is always more difficult."

Kresh sat down to pull his pants over his feet, but the fasteners had closed before he put them on. He fumbled with them a moment before they would reopen. "Damnation. Nothing is ever easy," he said, talking in equal part about the tactical situation and the difficulty of getting his own pants on. The storms in the desert were rare, but tremendously violent. Even a skilled pilot would hesitate to fly in such conditions. If Caliban went into the storm, odds were he would not come out. " All right, advise the aircars to maintain pursuit, but no heroics. We've had enough stunt flying. Break off the pursuit if it becomes dangerous. They are specifically ordered not to risk themselves or their craft. Remind them that we ought to be able to track him easily outside the city. No tunnels, no skyscrapers, no millions of robots to hide among.

"They arenot repeatnot to shoot down the aircar. They are ordered to capture, not destroy Caliban. If possible, they are to force him to land. I want to question him. He may be the only damned witness we have to the Leving assault.Do not destroy him. We can always do that later." Kresh stood up to pull his pants on. "Call off the citywide search," he said with a grunt. "Let the search teams get some rest and stand by to provide backup outside the city if need be."

"Yes, sir. I am relaying your orders now. However, my standing orders require me to remind you Tonya Welton is to be made aware of every major development in the investigation."

"We'll send her a memo in the morning. She's not going to hear word one about this. Not while she's a suspect, and not when we can count on her to blab everything she hears to Gubber Anshaw."

"Yes, sir. I quite agree, regardless of my standing orders. However, I am also required to remind you that your jurisdiction, and that of your deputies, is limited to the city of Hades. You and your subordinates have no authority whatsoever outside the city limits."

"To hell with jurisdiction. I want to get out on the jobnow."

"Yes, sir. May I take it, then, that you and I will join the pursuit personally?"

"Absolutely." Alvar struggled with the fasteners for a moment and finally got the pants closed. He pulled on his jacket and then noticed that Donald had laid out his holster as well. But there was something odd about Donald doing that. Robots as a rule did not handle weapons. The First Law difficulty was obvious-if Donald put a weapon in Kresh ' s hand, and Kresh used it to kill someone, then Donald had materially aided in harming a human being. And the blaster in the holster wasn't one Alvar had seen before. "What's this about, Donald?" he asked, picking up the belt and the weapon.

"You might wish to add your own blaster as well, sir, but I have a reason for asking that you wear that one. It is a training blaster. It provides an excellent simulation of a real blaster beam, but it fires nothing more dangerous than a rather spectacular burst of light."

"I see," Alvar said, although he didn't. "Might I ask why I should wear a training blaster on this job?"

"Sir, if you bear with me, I would beg leave to say as little about it as possible. Nothing may come of it. But I can foresee a situation where it could serve to test a theory of mine. If we find ourselves in such a circumstance, I will ask you to do just that-test my theory."

"Donald, I was not aware that you were programmed to speak in riddles."

"Yes, sir. I agree that I am being rather vague. However, I have very little confidence in my theory, and I believe it would be for the best if you were not distracted from the task at hand by worrying about unlikely possibilities. There is no absolute need for you to carry the training blaster."

Alvar Kresh held the holster in his two hands and stared long and hard at the robot. Donald at his most obscure was Donald at his most infuriating-but also, all too often, Donald at his greatest value. Donald had no doubt been thinking long and hard about this case, and it should come as no surprise that he had his own ideas, even if he was reluctant to reveal them just yet. But only a fool would ignore hints this clear from a mind that sharp. Kresh strapped on the holster, retrieved his own blaster from the drawer in which he kept it, and slipped it into a jacket pocket. It would be handy there, but his first reflex would be to reach for the training unit in the holster.

And in a pinch, it would be up to Donald to make sure that reflex didn't get him killed.

"All right, then," Alvar said. "Let's go."

CALIBAN had never before experienced true night, the exterior world, without the glare of artificial lighting. Strange, this world of darkness, this velvet nothingness that enveloped everything. Exciting, mysterious, frightening darkness. He could understand why the image of darkness appeared so frequently in his datastore. Humans had faced a great deal of darkness in their history.

And they had faced it without benefit of infrared vision, either. A mere act of will switched his vision system over from visual to IR range, and the surrounding blackness vanished. The heat-image of the ground below was plainly visible, but more important, his two pursuers showed up nicely in infrared, even if the two craft were invisible in the visible-light blackness of night. So much for the theory that the Sheriff would not pursue him outside the city. At least they were not firing on him. Perhaps they intended to capture him instead of killing him.

If so, that was all to the good, of course. It ought to make evading them easier-though they were bound to catch him sooner or later if he didn't do something.

There was a large weather system, clearly visible in infrared, roiling with power. He flew toward it as fast as he could, his pursuers getting closer and closer with every moment. It was going to be close. A sudden gust of wind buffeted his elderly craft, taking Caliban by surprise. The aircar twisted and dove, nearly flipping over on its back before he could regain control.

Another gust caught at his craft from another direction, but Caliban was ready for it this time. The storm wall was dead ahead. He could hear its roaring power, see the flickering traces of lightning that flashed across its interior. Now the buffeting was almost constant, and hard sprays of rain and hail clattered against the aircar, peppering Caliban as well. Suddenly the winds and the rain and the clouds seemed to gather him in, the 'powerful storm swallowing him up.

His aircar was thrown forward by a following wind, lifted up on high by a violent updraft, cast down again with equal violence. Sparks flew as something shorted out, and half the control panel went dead. The aircar was thrown sideways and nearly flipped over on its side before Caliban could force the protesting craft back to level flight. The noise and the force of the storm were incredible, the thunder crashing everywhere, the roaring impact of the rain against his body all-encompassing, devouring Caliban, making him one with the rain and the wind and the dark and the flares of lightning. The aircar was caught by a backdraft and thrown into a dive, heeling over to head groundward at tremendous speed. He struggled to pull up the nose, slamming over the lift control to maximum, the old car groaning and protesting, a deep, angry throbbing vibration suddenly coming up from somewhere in the drive section. There was a shuddering bang that rattled the whole car, and an abrupt drop-off in the vibration, as if something has broken clean off.

Caliban ignored it all, struggling to bring the nose up, straining to slow his headlong fall toward the unseen ground below. Slowly, slowly the protesting craft lifted its nose, groaning and shuddering in protest.

With shocking abruptness, the aircar broke through the base of the storm clouds, revealing the rough ground rushing up to meet it. Now at least the rain was pelting straight down on him, instead of smashing in from all directions, but even so, he had almost no visibility at all.

With a last heroic effort, the tortured aircar finally achieved level flight. But smoke was burgeoning up from under the floorboards, a thick cloud that would have blinded him if the rains had not kept it beaten down. The controls were balky and getting worse. The last of the status indicators flickered once, twice, and went out. The power was gone, and the aircar was suddenly a glider, and not a very good one. The aircar was going down, and there was nothing he could do about it. He struggled to slow the craft, to bring the nose up, trading speed for range and glide angle. But there was nothing left, nothing more he could do.

The car smashed into the ground, bouncing and crashing and skidding across boulders and sand of the rain-torn blackness of the desert.

ALVAR Kresh and Donald stepped out onto the rooftop landing pad of Kresh's house to discover they had rather unwelcome company just arriving. Tonya Welton was getting out of her own aircar, her robot, Ariel, right behind her.

"I'm going with you," Tonya announced. "You spotted Caliban. You are going after him. And I have the right, the power, the authority, to attach myself to any area of this investigation. I have the legal rights, and I will stand by them."

"How the hell do you know where we're going?" Kresh demanded, though he had figured out the humiliating answer even before he was done asking the question. Damn the Settlers and their arrogant technology.

"Your secure hyperwave communications aren't all that secure," Tonya said. "We monitor them."

"Didmonitor them," Kresh growled. "There will be a few changes madevery quickly. You seem to have blown your cover."

Tonya shook her head, dismissing a minor concern. "That is of no consequence. Not compared to the danger we are all in right now. There are any number of ways this case could touch off a political backlash and sabotage the terraforming project, and then this world would die. We wouldall die."

"We? Since when is it your world?"

Tonya looked up at him. Her eyes were bright and wide with fear and worry. "Since Gubber is in it. I am not going to abandon him, or let the world he lives on die. I intend to remain on Inferno, whatever happens."

"Lady Welton, I must suggest most strongly that you not come with us," said Donald. "There is no polite way of saying this, but you are a suspect in the case."

"All the old gods damn it! Of course I am! Don 't you think I know that Gubber and I are both suspects?" She stopped, her chest heaving, tears running down her face. "Damn it, don't you see? If he did it, and Caliban can tell us that, I have to be there.I have to know. I can accept it, either way. But Ican't pretend anymore in front of him. I have to know."

Alvar Kresh stared at Tonya Welton in frank astonishment. She was the last person in the known universe he would have expected to have such an outburst. It was hard not to think it would serve as a first-rate cover if Tonya were determined to come along for the purpose of silencing Caliban with a quick blaster shot.

But damn it, she had the legal authority to come along, and even if she did not, there was little he could do to stop her following along in her own aircar, short of shooting it out of the sky. But he did not have to make it easier on her.

"Very well," Alvar said. "You may come with us. But you will leave all your weapons and other devices behind, and submit to Donald performing a search to confirm this. You will wear clothing I will provide to prevent any attempt at smuggling of illicit hardware or weaponry."

Tonya Welton seemed about to protest, but then she thought better of it. "I am carrying no weapon, but I will submit to a search and clothes change."

It was Kresh ' s turn to be taken aback. Maybe she was in earnest after all. "Donald, get moving. Get her searched and dressedfast."

"Yes, sir. Though I would suggest there will be little point to haste." He pointed up into the northern sky.

Alvar Kresh looked and swore. The storm was coming on, moving south, huge and violent. Already the winds were whipping up. Damnation! No robot would allow a human to go up in that, and for once, Kresh was forced to admit that the robots had a point. It would be suicide to fly into that. Though he didn't like to think about that., For Caliban, his last hope of making sense out of this case, had flown into that very storm minutes before.