Doctor Who_ Castrovalva Part 3

'Approaching Hydrogen Inrush, Event One,' it said.

And then as she read it a new sentence appeared, in big capital letters: ENVIRONMENT BEYOND ENGINEERING TOLERANCES. Nyssa stared at the message. Its meaning was clear enough, but she had no idea what she was supposed to do about it.

If the heat and the tolerance warning were linked with this mysterious Event One, then it seemed that the sensible thing would be to find out what the Hydrogen Inrush actually was. She began a patient search of the data base. Like the walls, the keyboard was now hot to the touch, and she worked fast, hoping she would be able to track down the information before the system collapsed.

At first reading the entry under 'Hydrogen' didn't tell her anything that she didn't know already. '... abundant element, highly explosive in the presence of oxygen...

Found throughout the universe in its dioxide form as ice, water or water vapour...'

But when she came to read it again her attention was riveted by one phrase. 'Hydrogen is the basic const.i.tuent out of which the galaxy was first made...' The dreadful suspicion that had seized her in the Zero Room seemed to be confirmed.

Tegan arrived at that moment, very hot and distraught.

'Typical TARDIS, choosing a time like this for the air-conditioning to collapse.'

If only that were the trouble,' said Nyssa. 'It's not the inside of the TARDIS we have to worry about.'

'What else could it be?'

Nyssa led her over to the viewer screen. 'You'd better have a look at this.' Puzzled, Tegan duly read the entry on 'Hydrogen', thinking that Nyssa was being rather schoolmarmish about all this, and wondering why she couldn't just tell her whatever it was she had discovered.

But when at last she looked up from the small screen she knew why Nyssa was being so careful about breaking the news to her. You needed some technical understanding to realise the terrible thing that was happening.

The two friends looked at each other, and Tegan had the courage to speak first. 'This is a time machine... And the Master's turned it into a trap.'

So that was the terrible thing that Adric, or rather the image of him controlled by the Master, had done to the TARDIS co-ordinates. They were racing towards the First Event, the creation of the galaxy out of a huge inrush of hydrogen.

Nyssa nodded. 'We're heading straight into an explosion.'

'Explosion?' Tegan queried, as if a quibble could stave off the reality of the event. 'How can an inrush be an explosion.'

'We'll be entering it backwards in time,' Nyssa answered coolly. 'The biggest explosion in history.' And at that moment the TARDIS gave a sudden lurch, throwing the two girls against the walls, which were by this time very hot to the touch.

In the Zero Room the persistent tolling of the cloister bell had been nagging at the Doctor like an aching tooth.

Something was very badly wrong, and he had to find out what it was and put it right. Cautiously this time he began to nudge open one of the big double doors, leaning back against the other as it swung gently open.

When the first lurch came it sent the Doctor spinning out into the corridor. And then when the TARDIS began to shake he reached out for a handhold, the handle of a nearby door. It was not the most sensible thing to do, but by this time the Doctor was hardly in a sensible mood. The door swung open, connecting with his head, and he slid down it to the ground, unconscious.

Nyssa and Tegan had barely had time to recover and stagger back towards the console when the second lurch sent them flying again. Tegan grabbed for a handhold, which happened to be a console control. Random handling of the instrument panel was a dangerous business, and she was lucky that all that happened was that the door of the viewer screen slid open. But when she looked up and saw what the screen depicted she gasped.

The face of their hated enemy, the Master, grinned down at them and they saw a black-gloved hand waving in a gesture of farewell. As the image retreated, flas.h.i.+ng lights revealed something of the interior of his vehicle. The black walls, the gleaming instrument panel... and behind them, Adric, caught in the glittering web of steel mesh.

The Master spun away into the distant starfield leaving the Doctor's TARDIS to its fateful destination. The two girls stared in horror at the empty screen.

4.

Russian Roulette Long after the Master's vehicle had spun away into the distant starfield, Nyssa went on looking at the viewer screen, seeming to see there the hated face of the man who had killed her father and destroyed her whole planet.

Tegan stood beside her, anxious to do something, although it was hard to know what.

'There's only one thing we can do,' Nyssa said after what seemed like a long silence. She slammed her hand on the lever that activated the viewer screen, and the cover slid shut again.

'And then what?' asked Tegan.

Nyssa's response came coolly. 'That's all.'

'All! Hogwas.h.!.+' Tegan raised her voice indignantly.

'We've found the data bank-we can learn to fly the machine.' The TARDIS seemed to have taken note of her bravura, because at that moment it gave another enormous lurch.

Deep in the interior of the eccentric Gallifreyan craft the same lurch caused a chrome and gla.s.s medical trolley to waddle out through a door marked 'Surgery', and sent it rattling off down the corridor towards the point where the Doctor lay hunched up on the ground. By one of those useful coincidences that so often spiced the Doctor's life, the trolley carried on its top shelf a large tin box bulging with medical supplies. But as mischance would have it (and the Doctor always had his fair share of that as well) he was too profoundly unconscious to take advantage of the fact, even when the trolley thudded gently into his shoulder.

The tin box tottered precariously above the Doctor's head, while the TARDIS veered giddyingly in s.p.a.ce, speeding towards its doom. And then the Doctor chose to stir, which again was unfortunate, because as he tried to prop himself up he jogged the trolley. The dislodged box landed on his head sharp corner downwards and scattered its contents all over the floor.

The sudden well-defined pain dragged him back to consciousness. He reached for a nearby roll of cotton wool and pulled off a wad to dab on his head. The trolley, having delivered its load of emergency medical supplies, succ.u.mbed to further motion of the TARDIS and went rolling off along the corridor.

The Doctor tried hard to pull himself together; with all these bottles and pills at his feet there was no excuse to prolong the malingering. He certainly did not feel very fit, but he knew from centuries of experience that one's own feelings are not necessarily the best guide to the real state of things. He fumbled among the packets of pills and small bottles of liquid, raising each in turn to his eyes to study it carefully and see if it had a contribution to make.

And then the TARDIS began to shake again, as if there were a race of demons in the superstructure. In the distance the cloister bell tolled on.

From the safety and comfort of his own travelling machine the Master watched on his viewer screen the violent shaking of his rival's vehicle as all the stars of the starfield began to close in around it. Behind him the boy hung in the cruel mesh of the electronic web, able only to stare in horror at the fate of his friends and the s.h.i.+p that had carried him on so many adventures.

He heard the familiar chuckle he had come to dread, and looked down to meet a pair of dark eyes that seemed to pierce his skull and read his mind. 'You must control these dangerous emotions, Adric. They only cause you pain.'

The Master turned back to the viewer screen and adjusted a small k.n.o.b on the control panel. 'Besides which, your emotions interfere with reception.' Certainly something was causing small white streaks on the picture.

'Let us go in closer.' On the screen the image of the TARDIS swelled, and the tiny wires that riddled Adric's flesh hummed faintly with the surge of energy they sucked from the boy.

The Master studied the screen, but the quality of the image dissatisfied him. He closed a switch on the console and turned back to the Alzarian. 'You have something to say?' the mocking voice enquired. 'Well?'

'I'll fight you...' Adric managed through the pain. 'I won't help you harm the Doctor.'

'Such touching loyalty.' Condescension purred in the Master's voice. 'But no match for my voltages.' He adjusted a lever and the pain that surged through Adric's body cleared the picture on the screen. A second lever dissolved the screen into a blue mist as the poly-directrix lenses penetrated the outer plasmic wall of the TARDIS.

'Closer, Adric,' came the insidious, insisting voice. 'I want to see them.' The Master moved the lever again, the glitter of victory in his eyes.

The Doctor had inspected all the small bottles, but witch hazel, friar's balsam, distilled glycerine, peppermint essence and oil of bergamot, though each excellent in its way, did not, he felt, quite meet the present case. He was left with the last of them, a small green container with a label that uncompromisingly announced itself as: 'The Solution'. The Doctor shook his head. 'Ah, my little friend... if only you were.'

At that moment the oceanic heaving of the TARDIS threw up more flotsam, for down the corridor a splendid visitation came rolling towards him: a motorised wheelchair. 'Ah, Transport of Delight!' cried the Doctor, stretching out a hand as it cruised within his reach.

The smoke was growing denser in the TARDIS console room, and it was now very nearly too hot to breathe. Tegan knew the risks of meddling with the TARDIS controls- even the Doctor, who understood the eccentricities of the old Type 40 better than anybody, sometimes came unstuck.

But having brushed aside Nyssa's cautious reservations, she was determined to get a response from at least one of these myriad b.u.t.tons and levers. After all, she had flown her father's Cessna back in Australia, and that had seemed horrendously complicated before you got used to it. And the worst that could happen as a result couldn't be anything near as dangerous as the Hydrogen Inrush to which the TARDIS was so determinedly heading.

But in fact nothing at all happened, even when she and Nyssa had walked round the console twice trying every switch and lever.

Nyssa had already explained that there wasn't much point to all this frenzied activity. Even if they managed to adjust the trim of the TARDIS they still couldn't change course. They were already caught in the field of Event One, which was pulling them faster and faster towards inevitable destruction. It is all very well being in at the beginning of things, but not when you are hurtling backwards into it at the speed of light.

Tegan was slow to grasp the physics of the situation.

'This force-it's a sort of gravity?'

'The Time Force. It's like gravity, but many orders of magnitude more powerful.'

Tegan took this as agreement with her idea, and developed it. 'People escape from gravity all the time. All we need is some kind of rocket thrust.' She caught Nyssa's eye. 'All right, enormous thrust... There must be some way the TARDIS can do that.'

'We can't even develop thrust,' Nyssa explained. 'The temperature's defeating the automatic controls...'

Tegan looked round the oppressive, smoke-filled console room in despair, and silently appealed to the spirit of the TARDIS, or whatever you called the obstinate thing that drove it. Of the various responses she could reasonably-or unreasonably-have expected, the one that came was the most surprising of all. The small door that led to the corridors chose that moment to open, ushering in a crumpled cream-clad figure riding in an electric wheelchair.

'Doctor!' the two girls gasped together. And Nyssa added immediately: 'You must go back!'

The Doctor replied with a lively shake of the head.

'Smoke... heat... noise... Adrenalin! Neuropeptides...' He tapped the side of his skull. 'The brain's working.'

'Neuropeptides?' asked Tegan. 'What's he on about now?'

Nyssa knelt in front of the Doctor, looking at him closely. 'The excitement's changing his biochemistry. It's only temporary, what they call a remission, but perhaps he can help us.'

Certainly the Doctor had a high flush in his otherwise pale cheeks, but that might just have been the temperature, for the console room was like a Turkish bath in which someone was trying to light a bonfire. 'You're right,' said Tegan. 'Better take him back straight away. It's not safe.'

But Nyssa's scientific mind had by now had time to work on the possibilities and probabilities, and she shook her head. 'The Doctor's our only chance... unless we can find some way of getting the temperature down.'

The note of urgency in her voice seemed to strike a chord in the Doctor, for he sat upright, suddenly completely alert. 'Manual over-ride. Nyssa... I'll have to explain how to vent the thermo-buffer...' A long arm stretched out to draw her closer to him. 'Listen carefully.

My concentration may go again any minute...'

The poly-directrix lenses were focused sharply now, and although there was no means of picking up sound vibrations across so many pa.r.s.ecs of empty s.p.a.ce, the Master fancied he could hear the dialogue of despair as the two girls huddled around the Doctor.

From behind him, up on the web, the boy's voice came as a faint commentary on the silent picture: 'Doctor!'

The Master smiled thinly. 'I sympathise. This is all too easy.' On the screen both girls were kneeling in front of the wheelchair now, paying attention to some fruitless final observations the Doctor saw fit to make. The obstinacy of the man in the face of a.s.sured total defeat stirred the Master's admiration. 'A great pity. These facile victories only leave me hungry for more conquests.'

The TARDIS had ceased to fight the pull of the Time Force. Nyssa knew this meant that technically they had pa.s.sed the point of no return, and were headed smoothly on course to destruction. But she had to put the thought from her mind, and bury it under the urgent work of the moment. She concentrated on repeating the instructions the Doctor had given her: a thermal gradient of minus 800... reverse Kelvin effect... transition temperatures for the outer-sh.e.l.l coolants. She received his approval, and crossed quickly to the door that led to the corridors.

The chimes of the cloister bell came so regularly now that she hardly heard them, but she needed no reminder of the emergency, for the smoke stung her eyes until she could hardly see for tears. It smelled acrid, as if important components were beginning to burn behind the walls, but she kept to the route, moving quickly but not running. At the third junction she turned right, and then right again.

The roundel looked like all the rest, and had it not been for the Doctor's careful instructions she could have searched the corridors forever without finding it. The circular panel came out of the wall quite easily as she turned it, and somehow managed to remain illuminated even when she put it down on the floor.

Behind the panel, just as the Doctor had said, was a white s.p.a.ce, with a small silver pointer in the centre. The moment she reached in to touch it the dreadful clamour of the cloister bell stopped dead, and the silence fell on her ears like a sea of snow-drifts.

In the console room the Doctor heard it too, and stopped in the middle of rattling off rapid instructions to Tegan. 'Good,' he said, sniffing the air, as though he could smell the silence through the wreaths of smoke, 'The whole system is on manual now. This is where it gets dangerous...'

Tegan had written, in not very accurate Pitman's shorthand, '... and you'll always find it simpler if you go into hover mode first...' Her pencil paused over the notepad. 'You mean it's been perfectly safe up to now!'

The Doctor chose to ignore the joke. 'The temperature will start coming down fairly quickly. That's good for you and the TARDIS, but bad for me. Without the stimulus my neuropeptide level will fall to normal.'

'Don't worry, Doc. We'll get you straight back to the Zero Room.'

'Good. Now, as soon as full console functions are restored you'll be able to reprogram the Architectural Configuration...' He levered himself stiffly up out of the wheelchair. 'This bit's very tricky. I'd better show you.'

They leant over the console together and the Doctor ran very quickly through the rudiments of dimensioning theory, just enough to give some meaning to the string of tasks she would have to perform. Tegan nodded and said 'Uh-huh' even when she didn't quite understand, because she thought that theory was all very well, but she wanted to get on to the doing part of it.

She had to stop the Doctor's flow for one important question though. 'What I don't quite see is, how will it help to change the TARDIS rooms around?'

'The Architectural Configuration System does more than that. We can actually delete rooms.'

Tegan opened her eyes in surprise. 'Delete them! You mean, just... zap??'

'Exactly... zap. Enough zap, and you'll have your thrust.'

He directed her direction to a set of switches in a little niche by themselves on the console. 'Now follow this carefully.'

'You bet your life, Doc.'

The Master smiled up at Adric, gesturing towards the screen. 'Perhaps this little demonstration is giving you some glimpse of my real power.'

The boy stared back defiantly. Though weak and unable to move, his face gave fluent expression to his feelings.

'Power you're getting from me... My computations.'

Without any visible cue from the Master, the black wall suddenly unfolded to reveal something like a small escalating staircase, which rolled forward automatically.

The Master stepped onto the device, and to the accompaniment of a faint whirring sound was carried upwards until he could peer closely into Adric's face.

'Your computations?' purred the Master. 'In part, certainly. Even as an enemy you're useful. But how much more useful as an ally...' He looked into Adric's eyes, giving the invitation time to sink in.

Tegan read her notes again to make quite sure she understood what the Doctor had told her. 'So we're converting the ma.s.s of the deleted TARDIS rooms into momentum. And that should give us the thrust we need to get out of this Inrush thing.' She understood most of it, except what 'momentum' was.

'Ma.s.s in motion. Thrust, if you like. Time enough for lessons later.'

'But it means burning up part of the TARDIS?' The Doctor seemed to take it lightly, but Tegan found the idea very disturbing.

'Don't worry, it works,' said the Doctor, misunderstanding what was troubling her. 'We had to do that once with Adric to get away from...' And then he asked the question she had been dreading. 'By the way, where is Adric?'