He recalled Jo Grant, with her soft, pretty face, framed by her always perfectly groomed, blond hair. He remembered Tegan, Leela, Zoe and Jamie. Even Turlough, the only companion who had seriously tried to kill him, flittered in and out of images of Nyssa, Romana and Liz Shaw.

But the image that danced most frequently across the history of time was that of Adric, for he performed the most grotesque caper of all, that of the Dance of Death.

Adric who, despite possessing a mathematical skill equal to the twins, had always managed to aggravate everyone aboard the TARDIS with his childish antics denying him the thing he desired most: to be loved and accepted for what he was.

It was Adric who had been killed whilst trying to divert a freighter, controlled by the Cybermen, from crashing into prehistoric Earth.

Stubborn Adric, who had refused to leave the ship and had given his life to help others.

It was this memory that the Doctor feared most. Not only had he been forced to stand helplessly by, but the boy had died without the Doctor ever being able to fully praise, help or ultimately like. It was these feelings that made Adric the saddest and most painful memory of all.

The Doctor shook his head as though trying to shake himself free of the unpleasant image. It wasn't the time to remember such things. He had more urgent problems to occupy his mind.

Slowly he refocussed his eyes so that his gaze pa.s.sed through the gla.s.s part.i.tion and into the hatchery beyond.

The technicians had gone and the conveyor belt was stationary.

The level of lighting had also been reduced, creating dense, eerie shadows.

The sight made the Doctor feel uneasy and he climbed to his feet, crossed to the control box situated at the side of the part.i.tion and fiddled with one of the switches.

Slowly the lights came up inside the hatchery, forcing the shadows to hide. 'What's this?'

Azmael ambled over to join the Doctor. 'Mestor's hatchery.'

'Can we get into it?'

The elderly Time Lord operated another lever on the control panel and, as the heavy part.i.tion started to rise, Peri crossed the room and joined them.

'Why do you want to go in there?' she enquired.

'I'm curious.'

Peri glanced at Azmael and hoping for his support said: 'But do we have the time?'

If Azmael agreed with the question, he didn't care to pursue it, as he remained silent.

Neither did the Doctor answer. Something was aggravating him, gnawing at the back of his mind.

With the part.i.tion fully open, the trio entered the hatchery. As they scrambled past the conveyor belt, they entered the dark cavern which was the main incubation area. It was hot and sticky and gave off a pungent, fruity smell.

As their eyes became accustomed to the gloom, it became apparent that the cavern went on for miles. Packed around its walls were millions of eggs, each one fitting neatly and precisely into a purpose-built slot.

Cautiously, the Doctor moved to one of the racks and lifted out an egg. It was the approximate size and shape of a rugby ball and weighed about one kilo. Cupping it in his hands, the Doctor seemed to be a.s.sessing the egg, trying to work out what was wrong with it. For something was missing, something that was so natural and obvious it took the Time Lord a full minute to realise what it was.

Without comment, the Doctor handed the egg to Peri and quickly moved to another rack. Carefully he felt all the eggs housed in it, and like the first one, they were dry.

'Something wrong?' enquired Peri.

There certainly is. If these are gastropod eggs, why are they dry?

Where is the mucus, the jelly, the food which nourishes the young within?'

Peri shrugged and then looked down at the egg. It certainly was dry, but then the sort of slugs she was used to didn't come two metres high and talk!

'There's something wrong,' said the Doctor, s.n.a.t.c.hing the egg from his companion. 'This may be the answer we've been looking for.'

Peri and Azmael followed as the Doctor made his way back to the laboratory area. T must see what's inside this egg,' he said placing it on a work bench. 'I shall need a laser cutter.'

Azmael rummaged momentarily in a cabinet and handed the Doctor what he wanted. The Doctor immediately set to work, allowing the white hot beam of light to focus on a single spot of the rubbery sh.e.l.l.

But nothing happened.

Strange, thought the Doctor, there must be something wrong with the cutter. But careful examination proved that it was in perfect working order. So he tried again. But still nothing happened.

'What are you trying to do?'jested Hugo. 'Hard-boil it?'

'Hardly!' The Doctor wasn't in the mood for jokes. 'The beam of the cutter is as hot as a diamond is hard. It should have at least scratched the surface.'

As the cutter continued to ineffectually blaze away at the egg, an unpleasant slurping sound was heard to come from within the sh.e.l.l.

The Doctor switched off the cutter as the sound grew momentarily louder and then more unpleasant.

'Is it going to hatch?' enquired Peri.

'I don't think so.'

And, as though to prove him right, the slurping sound stopped.

The embryo only reacted to the heat,' said Azmael.

'Precisely what it's supposed to do. Only it isn't anything like hot enough yet.'

Puzzled, Hugo glanced at Peri, but she didn't understand what he was talking about either. 'You're talking in riddles, Doctor.'

'No he isn't,' said Azmael, beginning to see what the Doctor was getting at.

'Now you're both talking in riddles,' insisted Peri. 'What is going on?'

How best to explain an intuitive leap, whose inspiration stems from tiny disparate events and observations? It was possible he was wrong, but the rea.s.surance of Azmael's concurrence made it unlikely.

The Doctor was also aware that Peri and Hugo's own scepticism wouldn't help them to believe what he was about to tell them, especially after his eccentric behaviour since his regeneration.

But did it matter? Did any of it matter? Right or wrong in his a.s.sumption, Mestor had to be stopped.

In a quiet, even voice the Doctor began to relate how and what he had concluded.

At the safe house Azmael had said that Mestor had led an original army of several hundred gastropods. Not only had they taken over Jaconda, but they had reduced its once fertile plains to the scorched, barren state Peri and Hugo had earlier seen for themselves.

If so few gastropods could cause so much damage, it would take very little time to devour any produce grown on the two planets Mestor wished to cultivate. Yet only a few metres from them were millions of eggs awaiting the opportunity to hatch. Simple mathematics had told the Doctor that three small planets could not support so many hungry, greedy mouths. Therefore, he had concluded, Mestor's intention must be to extend his empire a great deal further.

So how best to do this?

As far as the Doctor knew, Mestor was not involved in building a ma.s.sive fleet of transporters, but he was interested in moving planets. One very effective way to distribute his unhatched eggs would be to create an enormous explosion. The easiest way to create the tremendous power necessary would be to explode a star.

And the simplest way to do that would be to send a hard, cold, ma.s.sive rock spinning to its heart.

In fact, a planet would do very nicely.

When the Doctor had subsequently discovered that the sh.e.l.l of the gastropod eggs could resist the maximum setting on a laser cutter - some ten thousand degrees centigrade - without incurring a scratch, Mestor's scheme seemed obvious. Domination of the universe with his own kind by exploding the Jacondan sun.

Such were the brutal, murderous implications of what was intended, that on completion of relating these facts, the Doctor wasn't certain he could believe them himself. But the sad, nodding head of Azmael confirmed he had come to the same conclusion.

The shocked silence of the group was broken by the squeaky, outraged voice of the twins. 'Mestor expected us to achieve that for him!'

The Doctor concurred.

'Outrageous!' stamped Romulus.

'Our genius was to be abused,' echoed his sibling.

But the Doctor was no longer listening. Instead of petty complaints what was needed now was a plan of action.

'Hugo,' ordered the Doctor. 'You must escort the twins and Peri back to the safety of the TARDIS. As Mestor still needs the twins alive, you shouldn't be under any threat of death.'

The young pilot nodded.

'And what do we do?' enquired Azmael.

'Deal with Mestor!'

The elderly Time Lord's face crinkled into a half ironic smile. 'Are we capable? Look at us, Doctor. I am old. I have even lost my ability to regenerate. .. And you... Your mind could cloud at any moment. We are hardly fit compet.i.tion for someone with the power that Mestor controls.'

'Better we die in harness, battling against the odds, than die in fear, finding menace in our own shadow. We have spent our lives fighting evil. We are certainly too old to give up that particular habit now.'

The Doctor's words sounded bold and exciting to Azmael. To die fighting evil was a romantic notion he had always held, but he was also aware of Mestor's skill at humiliating his victims before death.

There was little honour or romantic bravado in being nailed to a tree with your eyes put out, your tongue missing and the skin flailed from your body.

Still, thought Azmael, there was even less honour in dying afraid of a knock on the door or being scared of going out after dark.

He had vowed to destroy Mestor and now was his chance. With the Doctor at his side, he stood a greater opportunity of succeeding.

And with the knowledge of Mestor's ambition numbing his sensibilities, he was provided with a greater and more honourable motive than simple, petty revenge.

'I'm with you, Doctor!'

'Good man!'

The Doctor then turned to Drak. As he started to order him to go with the others to the TARDIS, he became aware of the blank, gla.s.sy-eyed look on his face. 'Are you all right?'

Instead of a reply, the Jacondan crashed to the floor.

Quickly, Azmael was at his side. It required minimal examination to establish Drak was dead, his mind burnt out.

'It must be the work of Mestor,' moaned Azmael plaintively. 'He must have used Drak as a monitoring point to overhear everything we've said.'

'Then Mestor will be expecting us.'

Gently, Azmael closed the dead eyes of the Jacondan. Although they had not been the greatest of friends, Azmael had warmed to Drak, especially since their mission to Earth. He had liked the way he had taken the twins under his wing, caring for them as though they were his own children.

Slowly, the elderly Time Lord stood up. If he had need of it, the death of Drak was yet another reason to destroy Mestor.

As the Doctor and Azmael left the laboratory, the Doctor picked up two small flasks of Mosten acid which he then secreted in one of his deep pockets.

Unlike most acids, Mosten acid doesn't burn or corrode, but ages whatever is immersed in it by a unique process of dehydration.

Professor Vinny Mosten discovered the acid which bears his name quite by chance when on an expedition to the planet Senile Nine.

Mosten wasn't a chemist but an archeologist who was visiting the planet to authenticate a recent priceless discovery of Senilian vases and figurines.

When presented with the discovery, Mosten had become immediately suspicious, partly because of the sheer size of the find, but also because of their pristine state. Further investigatin found the vases and statues not what they, were supposed to be, but modern copies, carefully aged.

Further investigation showed the reason for the deception: the planet was bankrupt. It had been the intention of the Senilians to pa.s.s off the discovery as authentic, selling the pieces to the highest bidder, thereby solving their immediate fiscal problems. They had also planned to 'discover' further items which they would exhibit, creating a tourist industry which would solve their long-term cash flow.

At least, that was the plan.

Mosten was so angered by the deception that he set out to discover how the Senilians had managed to age their pseudo antiques so skilfully.

Such was his determination that it didn't take him long to find the chemist who had invented the acid. With the aid of a ma.s.sive bribe, he was able to acquire two flasks of the unique liquid.

However, whilst travelling to the press conference where he was to publicly expose and denounce the acid, one of the flasks broke in his pocket. Unfortunately for Mosten, he aged and died in seconds.

When he arrived at the conference there was nothing left of him but a pile of grey ash.

Fortunately for the planet Senile, the second flask had survived and, on being a.n.a.lysed, was declared a breakthrough in the science of chemistry. No longer would incredibly hard substances such as modern alloys have to be drilled, carefully filed, subjected to controlled explosion or, in more extreme cases, simply left to weather away. With the careful application of the acid, any shape or depth of hole could be created quickly, simply, safely and, more importantly for money-orientated societies, very cheaply.