"But he seemed to forget what he was doing while he was doing it," Ace pointed out.

"It's a safeguard," the Doctor explained. "My people, the Time Lords, don't like to interfere in the affairs of other worlds. And the Matrix gives a person access to enough information to allow someone to meddle rather effectively. So whenever anyone uses the Matrix to get any specific piece of information, anything else that they might accidentally stumble across is wiped from their minds. He - me - had to enter the Matrix when Gallifrey was invaded by the Sontarans. But my memory of what I found there was completely wiped out, at least theoretically. So the warning about the Timewyrm must be pretty urgent, for me to have been able to keep it in my memory long enough to get back to the TARDIS and warn myself about it."

He sighed. "I just wish I had remembered enough to make it worthwhile."

"And what's a Leela?" Ace asked.

"Who, not what. She was a traveling companion of mine. You didn't imagine you were the first person I ever took along with me, did you?" "I hardly know what to think," she snapped back. "You stole my memories, remember?" "Of course I remember," he scowled. "You're the one with the slate-clean mind, not me. Try to concentrate. This Timewyrm must be something very important. I wish I knew what I wanted me to do."

Ace shrugged. "You'll just have to be very careful if we run into a Timewyrm."

"That's rather obvious," the Doctor said. "I could have worked that out for myself." He stared at her, and shrugged. "Let's see about getting you your memory back, shall we?" "That would be nice," she said, sarcastically.

"How did you manage to wipe my mind, anyway?" "I was clearing up some of the clutter in my forebrain," he explained, hovering over the telepathic circuitry. Decisively, he stabbed at a pattern of controls. "As I said, I'm a Time Lord. We live for a vast length of years by your standards. And in that time, we get an atticful of useless memories. Every few thousand years, we like to clean them out, so to speak. Edit out what we don't need, and leave plenty of room for new stuff as we go along."

"And what happens to the used memories?" she asked with interest. This was like nothing she'd ever heard about before - at least, as far as she could recall. "Do you write a book? My Lives and Times?" "Don't be absurd." He was trying to concentrate on his programming. "The TARDIS stores the important data. The rest are wiped. Pfft. Gone."

With sudden panic, she stared at the panel he was playing with. It seemed full of red lights. Her generalized knowledge told her that red lights were used as warning signs. "Is that what you've done with me?" she asked, gripping his arm and pointing at the console. "Have you pffted me out of there?" Shaking her free, he stared haughtily at her. "Of course not. There's plenty of room in the TARDIS's memory banks for the contents of that small mind of yours. It's just a matter of accessing it and - aha!" Grinning in triumph, he pointed at the little screen again. Ace peered at it: whatever language it was written in, she couldn't recall knowing it.

"I can't read that," she complained.

"Of course you can't," he agreed, infuriatingly. "It's in ancient High Gallifreyan. All the best computer programs are. But that's you, right there."

"But I want to be me right here." She tapped the side of her head.

"I'm getting to that. Come over here and put both hands palm down on these two metal plates." He gestured to the base of the telepathic circuits.

Warily, she held her hands almost in position. "Why?" she asked. She couldn't remember if she trusted him or not, and preferred to play it safe, given what she knew about his actions so far. A man - a Time Lord, she corrected herself - who erased everything you ever knew purely by accident was not someone to trust implicitly.

"You've got to make contact with the circuits, or I can't transfer those memories back."

"Well, you drained them out, and I was nowhere near this panel," she objected.

"You were asleep," he explained, with all the patience he could muster.

"And the telepathic matrix somehow overlapped your mind. Your defences were down, and you were relaxed. Now your defences are up, and you're very tense. So I need a good, clean contact pathway between your brain and the circuits. Do as you're told."

"When I get my memories back," she asked, annoyed by his att.i.tude, "do I like you?" "Everybody likes me," he told her. "Well, almost everybody."

When she gingerly placed her hands in position, he nodded, and tapped in the final codes.

Ace felt like she'd been kicked in the brain by a bad-tempered Cyberman.

She tried to scream and draw free, but she was rooted to the spot, frozen.

Through the pain, she could feel her mind expanding. Memories were flooding back, she supposed, but it just felt like she was being grilled over mental coals.

After an eternity, the agony was over, and she was free.

With a stifled sob, she collapsed to the floor.

"Bit of a strain, I expect," the Doctor said, without any obvious sympathy.

"Need a rest."

"What I need," she told him from the floor, "is a loaded submachine-gun and a target painted on your back. Or a can of nitro-nine. You can have a fifty yard start." "Ah," he grinned, entirely unmoved by her anger. "So you remember who you are now?" She considered it. Reaching into her mind, she discovered that she did know: Dorothy - G.o.d, how she hated that name! And she and the Doctor had taken off a while ago in the TARDIS - TARDIS: Time And Relative Dimension In s.p.a.ce. A sophisticated machine that looks like a dilapidated London Police Telephone Box on the outside.

Inside, its dimensions are vastly larger, and it is capable of traversing all the known boundaries of time and s.p.a.ce by pa.s.sage through the Vortex - they had taken off in the TARDIS from near her home. Perivale, West London. Not much of a home. They had fought the Master (image of a sneering, bearded face, elegant clothing and fangs) on the planet of the Cheetah people (smell of blood, pounding of feet, the thrill of the hunt, the...) "Yes," she said, unable to conceal the smile in her voice. "I'm Ace."

"Well, that's an improvement," he said.

Climbing unsteadily to her feet, she leaned on the console for support.

"Doctor, how could you possibly be so stupid?" she demanded wearily.

"What if I hadn't got my memories back?" "You'd have found some new ones," he told her blithely. "You're young and adaptable."

"You what?" Ace could hardly trust herself to speak. "This is important, Doctor. You have to know who you really are."

The Doctor made no reply. A shadow crossed his face, and he looked lost and alone. Ace decided to change the subject. "Well, I prefer knowing, all right? Anyhow, how do I know I've got all my memories back?" "We'll do a spot check, Where did you first meet me?" "Iceworld," she said, promptly. "I was a waitress. Tedium City. Boring job, boring people, I was dead chuffed when you turned up - a bit of excitement at last. And..." She broke off.

"Then there's something about Fenric ... He planned the whole thing. I was at school, in the lab, mixing up a batch of nitro, and there was this mega explosion... and I was on Iceworld. But it was Fenric who made it all happen, wasn't it?" "Yes," the Doctor told her, grimly. "It was Fenric."

"Have you been mucking about with my mind?" she asked, aggressively.

"Changing things about in there? Did you edit out some bits of it?" "If I had," the Doctor replied, "I'd have made you a lot less rude than you are.

No, you've got back whatever the TARDIS took from you. You're all you again - for better or worse.."

"Thanks a heap," she muttered. "I don't think I'll ever be able to go to sleep again in peace."

"I can put a few buffers into the circuits. Stop it from happening again. In fact -" He broke off as a low, booming sound filled the room. After a second, it was repeated.

Nothing in her memory gave any clue as to what the noise was. Ace turned to the Doctor, who looked almost ashen. "What was that?" "The Cloister Bell," he told her, grimly.

She couldn't remember any cloisters in the TARDIS. "Well, why's it ringing?" "I don't know," he answered. "It's not sounded since - since the Logopolis affair. When I died - the me you saw in that recording, that is. It only rings in the direst of emergencies."

That wasn't exactly rea.s.suring. "Like what?" Why was he always so frustratingly tight-mouthed with information that might be crucial? "Oh, the end of the Universe. Imminent death and destruction on a colossal scale. A regeneration crisis of painful proportions. That sort of thing."

Ace thought about it for a moment. Not good, clearly. But then with the Doctor so few things ever were. She realized that in one way having regained her memory was not so marvellous - it made her painfully aware of all her previous adventures with this strange traveller. "Then what could it be signalling now?" "How should I know?" He examined the controls.

"We're still in the Vortex, and there's nothing outside the ship. I don't know why it's sounding."

"You don't know much, and that's a fact," Ace told him in disgust.

"The d.u.c.h.ess in Alice's Adventures In Wonderland," he told her, after a moment's thought. "I know where you stole that quotation from."

An idea occurred to her. "Do you think this Cloister Bell thingy is connected with whatever it was you were warning yourself about a few minutes ago?"

Boom...

The Doctor started at the sound, and stared into nothingness thoughtfully.

"It would appear so, yes. The Timewyrm."

Booommm. . .

Worried, Ace glanced around. "It's... it's responding to what we say." .

"Of course it is," he told her. "It's the TARDIS, trying to communicate with us."

"Can't it do better than this? Or are we expected to play twenty questions to find out what the problem is?" The Doctor glared impatiently at her. "The TARDIS can't speak directly to us. Its intelligence is of a vastly different order to yours - or even mine. It's doing the best it can. Whatever is happening must be very drastic indeed. The Cloister Bell is a sort of warning signal it sounds to get my attention."

"Well, it's certainly got mine. Then what?"- He stared at the panel. A light was blinking, steadily. The scanner control... He glanced up at the screen set into the far wall, and it burst into life.

Ace jumped, and then stared at the face she saw there. "It's the Brig!" she exclaimed. The military bearing, the clipped moustache, the calm and efficient air were all familiar to her - Brigadier Alastair Lethbridge-Stewart, once head of the United Nations Intelligence Taskforce in Britain. But he looked younger here, and he wore his UNIT uniform over a much trimmer body than when she had met him.

"Doctor," the Brigadier said, in his precise, measured tones, "I need your help. Doctor?" Then the picture faded away into nothingness.

"A cosmic distress signal?" she asked him. "Did the Brigadier get your number from interstellar directory enquiries?" "Very funny," the Doctor snapped. He tried fiddling with the controls, but nothing happened. "No, there isn't any way that he could have done this. But why..."

The screen lit up again. This time, it showed a frightened young girl. She had long brown hair and was dressed in a Victorian-looking gown. "Doctor!"

she called. "Doctor! Where are you? Help me! Help me!" The girl glanced over her shoulder and screamed. Then she, too, vanished.

"What's going on?" Ace demanded. "Who was that?" "Victoria," the Doctor replied tartly. "A much quieter and less obstreperous travelling companion than you are. And she didn't ask as many pointless questions." He rapped his knuckles hard on his forehead. "Come on Doctor, think. Think!" Again, the screen lit up. This time, it showed a young man with long, wild hair, dressed in a kilt and wielding a claymore. "Doctor!" he yelled, in thick Scottish tones. "I canna see ye! Help me! Doctor!" Then, in his turn, he faded out to the white screen.

"Jamie McCrimmon," the Doctor said hastily, fending off the obvious question. "Another person who travelled with me for a while." He snapped his fingers. "Got it! Those are all events that happened in the past! The TARDIS is using my own memories, projecting them onto the screen..."

"But why?" Ace asked, frustrated. The more she learned, the less she knew.

"I don't know... yet. But there's got to be a reason for it all," he a.s.sured her. "The TARDIS never acts without a very solid reason." Ace snorted in disbelief.

The screen lit up again. This time, it showed a young girl of about Ace's age, with an elfin face, and thick, dark hair. She wore a loose-flowing gown, and stared out of the screen with a trusting expression on her face.

"Your temple travels through many times, Doctor," she said. "Truly, it is a wondrous thing you do."

"Katarina," he said swiftly. For a moment, Ace thought she saw a tear hovering on the edge of his eye, but then it was gone." She's dead, now."

"Temple," Katarina's image repeated. "Temple. Temple." Then the screen flashed a brilliant white. The blinding expanse was punctuated by a series of coordinates that looked familiar to Ace.

"Here!" she exclaimed. "That's the code you always set to get us to Earth!"

The Doctor nodded. As they watched, the numbers began to dissolve, flowing and vanishing as they did so. Eventually, the screen was pure white again. Obviously, it was over.

Ace glanced uncertainly at the Doctor. "What was all that about?" she asked.

He turned a haunted face towards her. "Well," he said, slowly, "unless I've very much misinterpreted the warning, I'd say that the TARDIS was telling us that deep in the Earth's past is something that could change the whole course of human history rather drastically."

"Drastically? How drastically?" "Drastically as in - BOOM. No more Earth..."

5: AMBUSH.

"I've got a very bad feeling about this."

Gilgamesh decided he couldn't ignore the comment this time. He paused and looked back at his friend, a resigned expression on his face. Enkidu took a little getting used to.

Not merely his mood swings, but even his appearance. He was tall, brooding and muscular, but hardly from the same stock as Gilgamesh and his men. Instead of the long, oiled beards of the men of Uruk, Enkidu had long, dark hair all over the exposed portions of his body. The bony ridges above his eyes projected forwards, his chin jutted out equally savagely.

Mysterious black eyes lay almost hidden in his face. Had he been somehow catapulted five thousand years into his own future, Enkidu would have been hailed with glee by archaeologists and anthropologists as a prime specimen of a Neanderthal Man, supposedly long-dead by this point in history.

"Stop grumbling, and come on," Gilgamesh told him. "We'll never get our work done if you hang back and complain all the time."

"It's too quiet," Enkidu said.

"I'm sorry, but I couldn't persuade any musicians to accompany us on a dangerous spying raid," Gilgamesh retorted. "Will you come on?" Warily, Enkidu moved up to join his king. He continued to scan the depths of the grove of date palms through which they were pa.s.sing. The seven-man patrol was now well within the boundaries of the land ruled by Kish, but there had been no signs of travellers or even workers yet. Enkidu mentioned this.

Sighing, Gilgamesh paused. "So, they finished work early. Who cares? It'll be sunset in a couple of hours, and I'd like to be inside the gates of Kish by then. They still have lions in this area, you know. And while I'm always fond of a good lion hunt, I don't want to get side-tracked from our mission."

"I suppose so," agreed Enkidu, looking as worried as ever. He took his duties as guardian of the king very seriously - too seriously, Gilgamesh sometimes thought. But at least he did pick up his pace somewhat.

Leaving the protection of the grove of trees the patrol made its way into the fields. Barley and rice were both being grown, and the crops looked healthy. Irrigation ditches, very like those of their own Uruk, watered the plants. Kish was clearly prospering, and heading for a well-stocked winter.

Shielding his eyes with his hand, Gilgamesh scanned the horizon.

Kish was visible in the distance - at least, its large stone walls were, and the occasional tower or roof jutting above the level of the walls. He was puzzled by an odd, orange gleam on the stones. On his last trip here, the walls had not looked like that . . . Something noteworthy certainly seemed to be happening here. Perhaps this trip wouldn't be a complete waste of time.

Just ahead of them in the fields was a cl.u.s.ter of palms about a small pool.

Gilgamesh nudged his friend. "Cool water, eh?" "And welcome," Enkidu agreed. He shifted his bow and quiver uncomfortably. "I'm parched."

Leading his men in that direction, Gilgamesh glanced up at the sun. They had plenty of time for a short rest and drink. Then they would head for Kish, and slip into the city before the nightly curfew. A friendly inn, a flask or two of barley beer, and maybe a willing wench . . .

They were jumped just inside the circle of trees. Soldiers of Kish had been waiting for them. As the patrol pa.s.sed between the closely growing trunks of the palms, the ambushers attacked.

Unable to draw their weapons or use their bows, Gilgamesh's men tried to fall back and gain time to unsheath their swords and battle-axes. But more men rose from the irrigation ditches, throwing off the shields covered with soil that had hidden them.

Gilgamesh and his men were surrounded.

Ace looked at the Doctor, appalled. "Aren't you overreacting a bit?" she asked hopefully.

"I never overreact," he replied grimly, ignoring Ace's outraged exclamation.