Has the show started yet?'

Diseaeda vainly tried to quieten the crowd. 'You've been drinking! Don't you realize we have children in the audience?'

'That's nice,' said the clown. 'Now I really must get down fro' here and -' He struggled pathetically for a few moments, and then looked pleadingly at Diseaeda. 'I appear to need some a.s.sistance,' he noted.

The monkeys pointed to another rope that extended down vertically from the darkness in the roof to a metal hoop set into the ground. The crowd began to cheer.

'Don't worry,' said Diseaeda. 'I'll let you down.' He undid the knot and, taking the strain of the man's weight, began to let the rope slip slowly through his hands.

The man ascended into the roof. Even Zoe was forced to smile at the Newtonian anomaly on display. The more rope Diseaeda released, the higher the clown went.

Diseaeda theatrically scratched his head and let go of the rope. The man disappeared from sight. The crowd hooted with laughter. Experimentally, Diseaeda began pulling on the rope, grimacing at the great weight he was moving.

The clown began to descend, this time tied by his hands and with a monkey hanging head-first from his feet.

'Just what is going on?' shouted Diseaeda over the roaring crowd.

Zoe closed the curtain.

'He's good, isn't he?' said Reisaz.

'A star performer,' agreed Raitak.

'And Diseaeda's not bad, either,' said Reisaz.

In Cosmae's absence Defrabax had taken to talking to himself. He found the habit a worrying one.

He sat at his desk, working through some calculations. A moth fluttered around the lamp before being consumed by the flame. Defrabax blew his nose, and tried the sum again.

A different result this time.

After several more attempts he crunched the paper into a ball and hurled it across the room. 'Where is that dratted boy?' he shouted. 'Everything is in place, but I still need that key!'

He'd checked with the house where Cosmae normally stayed when he was annoyed about something and had discovered that he'd been there for breakfast only. It was getting late, and Cosmae had still not returned. Whilst Defrabax had been serious about Cosmae getting the key back, he would never have sent the lad out if he'd known that there was any danger involved.

He got to his feet and paced the room, rubbing his rheumatic knee and muttering darkly. Then he pulled a long cloak around his shoulders and walked to the front door, locking the rear room. 'It's always me who has to pick up the pieces, isn't it?' he grumbled.

He walked out into the street and slammed the door. It was raining again. d.a.m.n this rain-sodden place.

A little way up the road he heard the sound of his door being broken down again, but chose to ignore it. 'Someone is forcing my hand,' he said gravely.

He continued his long walk towards the castle.

Cosmae watched as Jamie ran for the stairs which descended into the main cavern, and then quickly followed him. Jamie shouted his battle cry halfway down and, as the brotherhood turned at the unexpected intrusion, he hurled his dirk towards the large man.

The desperately thrown dagger caught the fat man in the shoulder. He dropped the hammer and held his shoulder to staunch the bleeding. Cosmae wondered if Jamie was as expert as he seemed or if he'd just been lucky.

Cosmae and Jamie started to run towards the altar, but they slowed as it began to dawn on them both that they had no weapons and no plan. The brothers turned to look at them, their faces blank shadows beneath the robes.

'You dare to intrude?' screamed the man in the golden mask. 'You dare to violate a meeting of the Brotherhood of Rexulon?'

Cosmae joined Jamie in backtracking towards the stone stairway. He believed in fighting valiantly for love, but not against such overwhelming odds. He a.s.sumed that it was Zaitabor behind the mask, but he couldn't be sure. 'What do we do next?' he whispered urgently.

'I don't know,' said Jamie. 'I get the feeling that we've walked into a trap.'

The man in the insect mask suddenly hurled a grey pellet towards Cosmae and Jamie. As it hit the ground it broke open, releasing clouds of stinking gas.

Cosmae turned to run but was immediately overtaken by the gas. He placed a hand over his mouth and tried to hold his breath but something dry and powerful flooded into his lungs. He struggled for breath, his chest held by a giant fist.

Choking, he fell into the sea of grey and found wondrous silence.

They had been trudging through the tunnels for hours.

The metal corridor that had so excited the Doctor led only to a room of old bricks and cobwebs. The Doctor was sure that his hypothesis was correct, but as yet they had found no more evidence of the ancient civilization.

The Doctor sat on a boulder and waved for Himesor to stop. 'I must rest for a few moments. I'm very tired.'

'Very well,' agreed Himesor. He motioned for his men to halt.

The Doctor, panting, removed his helmet. He breathed deeply, sniffed the air, and then coughed into his handkerchief Himesor looked on, concerned.

The Doctor blew his nose, and then beamed at the Grand Knight. 'As I thought. The air is breatheable now. We don't need to wear the helmets.'

The knights removed their helms and settled down into groups, some talking quietly. Himesor sat next to the Doctor, making notes on the back of the map. 'We're into uncharted tunnels now.'

The Doctor looked about him at the smallish cave in which they had come to rest. The roof was invisible in the shadows, although the tips of stalact.i.tes glinted in the torchlight. It appeared to be a natural construction rather than part of the sewers or even the old city. 'I was expecting to have found your menagerie by now, I must admit,' he said. 'Still, let's hope we can get back, eh?'

'That should not be difficult. I've tried to keep a note of the landmarks we pa.s.s.'

'We're not alone down here, by the way,' said the Doctor casually. 'I keep glimpsing a humanoid figure moving in the shadows. It's checking on our progress.'

'Are you sure?' asked Himesor. 'I myself have seen nothing, and the knights that we have brought with us are the finest I know.'

'Well, I do have a slight advantage over you all,' said the Doctor. 'I know what I'm looking for.'

'And that is?'

'An android utilizing accepted stealth procedures.'

'A what?'

'A metal man following orders to hide in the shadows.'

Himesor paused for a moment in thought. 'I was about to say that I don't believe you,' he said, rubbing his chin. 'But you were right about these artefacts.'

'Marvellous bits of work, I'm sure you'll agree,' said the Doctor. He fiddled absently with his helmet.

'My interest in their creation is only matched by my increased awe at the beneficence of the Higher,' stated Himesor before getting to his feet. 'You said that the metal man was following orders. Whose might those be?'

'I have no idea,' the Doctor replied. 'But if Defrabax really does have a homunculus, I would imagine that it's actually an android. And whatever its orders are, it will follow them with immense efficiency.'

Himesor nodded, and then turned to his men. 'Be on your guard for a creature moving through the shadows. The Doctor thinks that -'

Something huge and dark landed on the Grand Knight, knocking him to the floor.

In the blink of an eye the knights were surrounded by a large number of moth-like creatures. As tall as men, their huge bony wings of orange and grey bore them gently to the ground with barely a sound. A number of knights reached for weapons, only to be clubbed to the ground by the creatures' powerful arms.

The Doctor turned to run, but was faced by two glittering compound eyes atop a damp maw of interlocking mandibles. The animal hissed and then lunged at the Doctor.

With a single movement it smashed him to the floor. The creature leaned over the Doctor, as if to bite him.

The Doctor slipped into unconsciousness. Far from finding the menagerie, it seemed that some of the creatures had come to find them.

Nine.

There was an acrid taste at the back of Cosmae's throat and a suffocating pressure on his lips and nose. So . . . He must have been out drinking and collapsed. That wasn't so bad.

The floor beneath him steadied. He turned his face to one side and breathed deeply as the room continued its travels without him.

Oddly quiet for a tavern, though. Perhaps he'd been taken home and Defrabax had left him to sleep on the floor in punishment. Whatever, it was obviously time to get up.

Time to open his eyes.

They remained closed. His eyelids felt as if they'd been glued together. He was lying uncomfortably on one half-numb arm. He moved what he hoped to be his hand into position, and began to rub his eyes.

The blood flowed back into his arm, surging with little pinp.r.i.c.ks of pain. He groaned as his eyes fluttered open.

There was a lot of light bouncing into his eyes from the floor. He stared at a whorl in the grain of the wood, observing the dark cracks and fissures and pathways, and then raised his head.

In that moment the memories came flooding back to him.

One of the Knights of Kuabris stood over him, impossibly tall and swaying from side to side. Cosmae blinked, and the image stabilized.

'Welcome back,' said the voice. A hand extended down towards Cosmae, which he instinctively reached out for.

The young knight hauled Cosmae to his feet. 'Your friends will recover shortly. And then perhaps you can tell me what you're doing in the castle, and how you managed to hide the girl from us for so long.'

Cosmae tried to reply, but his throat felt parched. He licked his lips and tried again. 'Girl?'

'You did well to liberate her from the dungeons. A pity you couldn't escape from the castle.'

'We didn't rescue her.'

'No?'

Not from the dungeons.'

'Who did?'

'The brotherhood.'

'Say that to Zaitabor,' snapped the knight urgently, 'and he will spill your guts for heresy.'

'Zaitabor is their leader. We followed him and the jailor into a secret chamber beneath the castle.'

'Zaitabor? That's ridiculous.' The knight helped Cosmae to a low leather-covered couch in the corner of the room.

Cosmae noticed for the first time that he was in some kind of office. He saw Jamie and Kaquaan still unconscious on the polished floor, and then closed his eyes until the splashes of colour receded. 'I feel awful,' he said. 'What happened to us?'

'You were found in one of the corridors that connect the towers. Unconscious, in a heap on the floor.'

'A kind of gas affected us. A pellet. The leader of the brotherhood . . .'