Such strength of emotion was alien to Zoe. Despite the Doctor's playful cynicism she still felt that logic was a vital part of any civilized person's mentality. But did she feel this simply because she was lucky enough not to have experienced the death of someone very close to her?

The trouble with the long journey - and the twins'

taciturnity - was that it gave Zoe a lot of time to think. She wasn't sure if she welcomed the prospect.

'Tell us again about your friends,' said Raitak suddenly.

Reisaz jumped as if waking up from a deep sleep.

Zoe reached down to pat the horse, not sure who was the most apprehensive. 'The Doctor is a traveller from . . . Well, I'm not quite sure where, actually, but I think it's somewhere very far away. Very advanced. I don't think he likes his own people much. He prefers to explore and put things right where he sees evil at work. He's very good at that. He b.u.mbles around until things become clear to him. It can be frustrating sometimes. But I've missed not having him around the past couple of days.'

'And the boy you spoke of? I think you said he came from your world.'

Zoe nodded, remembering an earlier conversation. 'He comes from my past. The Doctor travels in time, you see.'

'Really?' said Raitak. 'If the knights were to discover that .

'If the Doctor has any sense he won't tell the knights too much about the nature of his travels,' said Reisaz.

'Why not?' asked Zoe.

The twins tried to spur their horse to quicken its pace.

Raitak turned to look at Zoe. 'One of the mental att.i.tudes that the knights promulgate is a concentration on the present moment as if unconnected to past or future. It's a fantasy, of course. The moment someone talks to you of the preceding day or how much money you have for food tomorrow the whole thing comes tumbling down.'

'And even the knights need to plan: to build buildings or to recruit new members,' said Reisaz.

'But if you could live just for the moment,' said Zoe, struggling with the concept, 'you'd be entirely isolated from pain and suffering.'

'A coward's way out,' said Raitak. 'You need to confront pain and suffering and strive to defeat them. Your obligation is to make sensible plans for the future and to learn from the past. That's why the knights are so cold and inhuman: they have no inclination to establish deep relationships. These things can only happen over a period of time.'

'They certainly don't like people enjoying themselves,'

said Zoe. 'I was arrested for no good reason at all.'

'They're a mirthless bunch,' agreed Reisaz.

'It must have been very frightening for you,' said Raitak with an unusual tenderness. 'Coming to somewhere new and then suddenly finding yourself cast into a dungeon.'

Zoe smiled, the memories already beginning to recede.

'Even when travelling with the Doctor things don't always go well.'

'That's everyday life,' observed Raitak.

'I'm curious,' said Zoe. 'Why did you ask about the Doctor and Jamie?'

'We might have to fight those monsters together. If your life depends on someone it's good to know a little bit about them.'

'You're convinced that there will be more of those things?'

'I just have this feeling,' said Raitak solemnly.

The Dugraq scout knew of a secondary system of caves and tunnels that lead on to the surface, entirely bypa.s.sing the poisonous sewers. The Doctor and the disguised android followed close behind the little creature. The android scanned their surroundings for movement, alert for wandering Taculbain or Rocarbies.

The subterranean world was quiet, and darker now the power station was off-line. The android had found a couple of battery-operated torches before they left the building and the Doctor took these. He alone needed them.

The little circle of white light illuminated collapsed brickwork, faded plaster and finally the damp walls of natural caves. When the Doctor heard what sounded like a waterfall to their left the torch's beam proved too feeble to illuminate it.

For a long time the Doctor shadowed the dim figure of the Dugraq exactly. At one point he followed the skipping creature over a narrow ridge of rock. It was only when he safely reached the end that the Doctor wondered how deep the drop on either side had been.

They emerged from a narrow tunnel into a cave that was dappled with light. Even the Doctor could now see the way forward, a huge opening of yellowish brightness.

'You get a fine view of the city from here,' said the Dugraq conversationally as they emerged from the tunnel.

'At least, when it isn't raining.'

'Fresh air, with no matter how much rain, will suit me down to the ground,' said the Doctor.

Soon they stood blinking on a chalky hillside where long-tailed sheep nibbled at grey gra.s.s. There was a strong breeze on the Doctor's face, and the closest part of the city to them, at the base of the hill, contained the Furnace. Its unfiltered fumes would have explained the dusty state of the gra.s.s.

However, it was clear even from this distance that the Furnace had been so badly damaged as to be beyond repair.

An entire brick chimney had crumbled along the full length of the building. Another had split and twisted. The majority of the walls of the building itself had been destroyed but inside was a tangle of metal and brick.

Although the sun was still hidden by one side of the valley, the early morning light softened some of the city's ugliness. The grey rain-bearing clouds had receded, at least for the moment.

'Meteorologically speaking,' announced the Doctor, 'it could be a nice day.'

The android's keen senses picked something up, and it slowly scanned the sky. 'Look there,' it said, pointing.

The Doctor squinted and saw dark figures climbing into the sky. Soon there was a hazy strip of them, extending from the opposite hillside and towards the castle.

'Taculbain?' he asked.

The Dugraq nodded. 'I've never heard of them coming out into the light before. I suppose it is possible for them to function but it must require great concentration.'

'Then whatever they're doing is very important,' said the Doctor. 'We haven't got much time. Let's find Defrabax and go to the castle. I don't like the look of this at all.'

Defrabax could feel the city's panic. The mental openness that genuinely elevated him above most men allowed him to experience the emotions and images remotely. Mothers pulled children indoors from yards and bolted doors behind them. Working men dropped their tools and cowered under roofs in fear. The sky was black with the humming wings of the moth-creatures. The cry quickly went round: 'More creatures from the menagerie! We are doomed!'

Where normally his mind was full of human strivings and plans now Defrabax saw with sudden crystal clarity the first of the Taculbain alighting at the base of the castle. The moth-creatures landed and gently folded back their great wings. They filed slowly into a cave at the castle's base.

They chirruped loudly to one another when the excitement became too great. Defrabax did not understand their clicking language, but he felt the meaning in the depth of the great cry: 'Soon our Queen shall be restored to us!'

The images faded.

Defrabax stood watching the approaching figures as resolute as a statue despite the wind that tugged at his hair and the fog that danced around his feet. He leant against a large staff, as colourful a figure as the city could tolerate.

The man he had seen on the communications device came and stood next to him. They both silently observed the city from the lower hillside.

'I want you to know that my intentions were honourable,'

said Defrabax.

'I know,' said the man who called himself the Doctor.

'We've both managed to distract the other from the true business at hand.'

'And that is?'

'The Taculbain,' said the Doctor. 'Or, rather, the things they've done to have their Queen returned to them.'

'Only one man knows what they have been ordered to do,'

said the magician, 'and that is the knight who used Kuabris robes much as you did to penetrate the menagerie. And yet I sense that the Taculbain have completed their mission.' He lifted a finger and traced it along the line of the moth-men as they flew towards the castle. 'I think that they are about to receive back their Queen.'

'We must go to the castle,' said the Doctor.

Defrabax nodded, deep in thought. 'At this moment all paths lead to the castle.'

Jamie and Kaquaan had investigated the long tapestry-covered corridor, searching for the secret door that led down to the Rexulon chamber. Jamie was disgusted when he found that he had been so simply tricked: two of the great tapestries had been swapped. The door, closed this time but not locked, now lay behind a bizarre family portrait of tiny st.i.tches.

'I should have known,' Jamie had said, disappointed at himself.

Kaquaan had gently rea.s.sured him, steering him towards the door. They had descended quickly and, although a number of brothers were already a.s.sembling in the main chamber, had found themselves alone in the changing room.

Disguised with Araboam's robes as best they could, they then donned the red cloaks and hoods of the Brotherhood of Rexulon.

Now they stood in the midst of the brothers, waiting for the ceremony to begin.

Jamie's memories of the first meeting were flowing back like an unstoppable spring tide. He remembered seeing Kaquaan on the altar, the smashed machinery, the man with the insect mask, everything. He blinked and gritted his teeth and forced himself back into the present.

This time the leader - Zaitabor - was nowhere to be seen. Jamie wondered how long a locked door and a bashed head would keep Araboam out of action. He hoped that it would be just long enough to allow him to disrupt another ceremony.

He noticed a tunnel in the cave wall towards the far side of the room. He was sure he hadn't seen it on the previous day, so perhaps the oily torch that burnt just above it was a recent addition. The flickering light caught the first of a mult.i.tude of moth-creatures who walked slowly into the chamber, standing in rows much like the brothers. Jamie stifled a cry of surprise and heard Kaquaan do the same.

The brothers, their own ranks swelling by the moment, were too preoccupied to notice. Some had already started chanting and swaying.

Jamie stared at the altar and hoped that the ceremony would start soon. He had given Kaquaan the sword. His own hand rested on the blade he trusted most. This time things would be different.

The streets were deserted and silent but for the sound of crying children, m.u.f.fled in back rooms and soothed in tiny cribs. The Doctor and the others moved unhindered through the streets and towards the castle, although the Doctor felt sure that the terrifying appearance of the android would have been enough to ensure their safe pa.s.sage.

As they neared the base of the castle the last of the moth-men alighted and strode into a dark pa.s.sageway set into the rock on which the castle sat. The tunnel was so obvious that the Doctor concluded that this secondary exit was normally hidden in some way.

'Let's hope we find some answers,' the Doctor said, 'wherever the Taculbain are going.'

The Taculbain had no need for artificial light but the Doctor switched on his torch as he stepped inside the entrance. The marks of the tunnel's construction were clearly visible, and the ascent was gentle. The moth-creatures were already well out of sight.

A few moments later the Doctor noticed that the tunnel was becoming brighter and switched off his torch. He crept forward slowly. He knew that he could rely on the android and the Dugraq to proceed silently but was much less sure of the old man's dexterity.

At length the Doctor began to hear m.u.f.fled voices. The tunnel was beginning to widen, and moments later rounded out into a large chamber, lit by flickering torchlight.

The Doctor and the others stepped quietly into the cave and surveyed the scene.

In front of them were rows and rows of Taculbain, stretching into the darkness at the edge of the room. The Doctor knew that, having lived in the caves for so long, the creatures' senses would be very acute, but so far he and his companions had gone undetected. The lines of carefully folded wings remained motionless.

The chamber inclined down slightly from the Taculbain and towards a flat central area dominated by an altar. On its surface was strapped a struggling young man the Doctor did not recognize.

On the opposite side of the altar was a large gathering of red-robed figures, variously chanting and shaking. Similar garments were worn by the tall man at the head of the altar.

He wore a golden mask of an insect's face and the well polished armour of one of the n.o.blest Knights of Kuabris.

He held aloft a huge weapon resembling a war hammer and an attentive hush fell across the chamber.

'Brothers and helpers, we are here to celebrate a turning point. The Brotherhood of Rexulon now has the power to overthrow the men of evil and let the light of the Higher shine across our land!'

The Doctor thought that he recognized the voice as being Zaitabor's, although there was a puzzling stiffness in the man's movements.

'Our friends are here to receive back their Queen,'

continued the leader of the brotherhood. 'They have faithfully followed their orders, though they did not know what they were doing, and they shall receive their reward.'