For one moment, Valgard was revisited by the fleeting glimpse that he'd had in the storeyard, his own face looking back from the other side of the line. 'You couldn't make it stick,' he said.

'Oh, but I could.' Eirak's fingers drifted lightly over some of the papers on his desk, touching them, almost loving them. 'How long would you last without a food ration? Or Hydromel?'

Valgard was beaten, and he knew it. Eirak had the power to withold the symptom-suppressing drug simply because the others all knew how much they needed him. When Valgard said nothing, Eirak went on, 'Get Sigurd and check out the liner. And forget about Bor, he's taken the easy way out.'

Nothing happened.

Eirak met Valgard's eyes and repeated, with a steely edge, 'Check the liner.'

Valgard turned and walked out.

The fifth block that they tried carried maintenance details for the liner, and several of the diagrams were given over to breakdowns of the corridor systems on each deck. They weren't exactly a tourist map, but they would do.

'It looks complicated,' Nyssa said.

'Like a maze,' the Doctor agreed. 'No wonder we got lost.' He stared for a while, fixing the details into his memory. There was a certain pattern in the layout of the pa.s.sageways, but it would have taken a long time to perceive it by wandering around. The diagram couldn't tell him where to find the TARDIS, but it would at least prevent them from wandering in circles as they looked for the link.

'We can put a bit more method into the search this way,' he explained when Kari asked him about the computer's usefulness. 'We can't afford to waste any time on uncertainties, now we know that there's disease around.' He was about to say more, but the lights went out.

'Everybody down!' Kari shouted, and such was her tone of command that everybody went. She whispered something else, and Olvir did a silent sprint across the control room to take up a position beside the door, burner at the ready.

As the Doctor's eyes slowly adjusted to the new light levels, he realised that the liner had simply returned itself to the state of readiness it had shown on their arrival. 'What's happening?' Nyssa wanted to know, and the Doctor nodded towards the control centre under the window. Before he could speak, the liner's automated voice was booming all around them.

' Attention Attention,' it said. ' Preparations for departure will begin Preparations for departure will begin with stage-one sterilisation. Unprotected personnel are advised with stage-one sterilisation. Unprotected personnel are advised to leave this liner immediately. No return will be permitted. to leave this liner immediately. No return will be permitted. ' '

'No one outside,' Olvir reported.

' Terminus Incorporated will accept no responsibility for the Terminus Incorporated will accept no responsibility for the consequences of ignoring this warning. Stage-one sterilisation consequences of ignoring this warning. Stage-one sterilisation is now commencing. is now commencing. ' '

The Doctor and Nyssa exchanged an apprehensive look.

It was quite a relief for Tegan and Turlough to come into an area where they could at least stand, even though they had to hunch a little to avoid banging their heads. The service core, as Tegan had named it, was a metal cage with a walkway floor that appeared to run the full length of the ship. It was obviously intended to give access to various underfloor areas, and because of this it seemed likely that they'd soon come upon a more orthodox way out.

'Maybe we're safer down here,' Turlough said, remembering what they'd seen only a little while before, but Tegan was doing her best to put this out of her mind.

'Come on,' she said, and started off ahead. There was some light, but most of it came from bad shielding where there should have been none. Turlough was slow in following; when Tegan looked back, she saw him standing and inspecting the floor beneath him.

'What's the matter?' she said.

He seemed hesitant, but he stepped forward. 'I felt the floor move...' he began, but before he could finish he was gone.

The walkway floor was no more than a series of thin alloy sections bolted to an underframe, and one of them had been loose. Tegan had stepped on its centre, but Turlough had put his weight too close to the edge - it had hinged under him as quickly and efficiently as the slickest trapdoor and dumped him through the resulting gap.

Tegan dashed to him. He was hanging onto the edge, his knuckles whitening as they fought for a grip where there was none. In the long darkness below him, the breakaway section was still falling. His hands slid a couple of inches and his legs kicked free in s.p.a.ce, but then Tegan grabbed both of his wrists and held him firm.

There was a booming crash, far-off and echoing.

Tegan pulled as hard as she could, but she was holding Turlough's weight almost unaided.

'Don't kick!' she said. 'You make it worse.'

Turlough did his best to be calm, even though his heart was racing. He tried to let himself swing free.

Tegan hauled again, and they made a few inches enough for him to get a fingerhold over the next join in the flooring. Now that he could help, Tegan reached over and grabbed a handful of his collar. She got a handful of his shoulder too, but he didn't complain. Slowly, his muscles singing like violin strings, Turlough came up and over the edge to safety.

They lay together, gasping. Tegan was still holding him, as if there was some danger that he might slide back. The only sound besides their ragged breathing was the howl of moving air in the vast s.p.a.ce below.

But then it slowly became clear to Turlough that the added rumbling that he'd been taking for granted wasn't simply the blood pounding in his ears.

'What's that?' he said, wondering if it was the working of his imagination, but Tegan had also heard something.

'I don't know,' she said. 'I don't like it.'

They barely had time to duck before the high-pressure sterilising gas was on them.

Kari's suggestion for speeding up the search for the TARDIS that they should split into two groups and keep in contact via the hand-radios hadn't really found much favour with the Doctor, but with the new urgency that had been added to the situation he really had little choice. Nyssa insisted that she'd be safe with Olvir, and so the Doctor reluctantly agreed.

'See you at the TARDIS,' Nyssa said, before she and Olvir disappeared from sight.

Kari was about to set off in the opposite direction, but the Doctor held her back for a moment. 'We can't waste time,' she protested.

'I know,' the Doctor said, 'but there's something we have to understand before we go any further.'

'What?'

'It doesn't matter who finds the TARDIS first. But n.o.body gets left, dumped or abandoned. All right?'

Kari hesitated. She seemed almost evasive, and it was obvious that she was overcoming her most immediate response. 'Of course,' she said eventually.

Ah, well, the Doctor thought, at least she's learning at least she's learning.

They moved out.

The search proceeded at speed, both parties moving in parallel around opposite sides of the liner. Olvir almost ran all the way, as if he felt he had something to prove, but the main consequence of this was that Nyssa found it harder and harder to keep up.

'I have to stop,' she said eventually.

'We can't,' Olvir told her. 'Come on.'

'Please...' She stumbled, and Olvir had to catch her.

It was then that he realised that his haste could actually defeat the object of the search. 'I had a dose of temporal instability,' she explained trying to catch her breath. 'I've been feeling bad ever since.'

He helped her down to sit on the floor against the corridor wall. 'A minute,' he said, 'no more. I'll tell the others.' And then he crouched beside her and unclipped the radio from his belt.

As soon as he switched it on, he knew that any attempt to communicate from this part of the ship would be pointless; the air was filled with a weakly pulsating interference from the radio's speaker.

'We've got a problem,' Nyssa said quietly.

'It's just leak interference,' Olvir a.s.sured her. 'Bad shielding on the engines somewhere.'

'That's not what I meant. Look.'

So Olvir looked, and got his first view of one of the liner's drones.

It stood squarely in the corridor before them, with the low-level lights glinting on the blades and drills by its sides. These were the only parts of the liner that Olvir had seen which didn't look shabby. It seemed to be waiting for something.

'There's no need for panic,' Olvir said, hoping that he sounded confident.

'I'm not panicking. I'm ill ill.'

'Can you stand up?'

'The problem is breathing.' Nyssa fumbled at her bodice in the shadows. Something ripped, and there was a clink of metal as something dropped to the floor.

'Don't make any sudden moves,' Olvir said. 'I don't like the look of those weapons.'

But Nyssa was starting to sound impatient with him.

She couldn't fight the reason for her discomfort, and Olvir just happened to be the next in line. 'They're not weapons,' she said, 'they're tools. It's a maintenance robot. Anyone can see that.'

'So what's the problem?'

'They're sterilising the place, and we're in the way.'

Olvir thought it over. If the drone really was no threat, then all they'd need to do would be to get up and walk away. It hadn't moved.

'Let's go,' he said and, moving slowly, he helped Nyssa to her feet. He couldn't help noticing that she leaned on him heavily. She came up into the weak light of the corridor and turned her face towards him.

She'd grown paler. Her skin was almost white, and her lips had darkened. Olvir felt a terrible wrench inside as he realised where he'd seen such a face before. He released her, and stepped back in horror.

'Olvir,' she said, alarmed, 'what's wrong?'

But Olvir could only shake his head. He couldn't speak. As if it had now received the signal that it had been waiting for, the drone moved forward.

And as it moved, the control voice echoed again around the ship. ' Attention Attention,' it said. ' This is the final This is the final warning. All Lazars and any other personnel must disembark warning. All Lazars and any other personnel must disembark immediately... immediately... ' '

(The drone extended a three-fingered clamp towards Nyssa, reaching for her wrist.) ' Stage-two sterilisation is about to begin. Drones will give Stage-two sterilisation is about to begin. Drones will give a.s.sistance to those Lazars requiring it... a.s.sistance to those Lazars requiring it... ' '

(Gently, it began to draw her away from Olvir; he did nothing to prevent it.) ' All other personnel must leave immediately... All other personnel must leave immediately... ' '

(Nyssa called for his help, but he could only stare as the voice continued.) ' All Lazars must comply with the drones. All Lazars must All Lazars must comply with the drones. All Lazars must comply with the drones. Stage-two sterilisation is about to comply with the drones. Stage-two sterilisation is about to begin. begin. ' '

Olvir stood alone in the corridor, though in his mind he was somewhere else. His father and his uncle were talking downstairs. Papers were being drawn up, some kind of loan was being agreed. His father and his mother were arguing. It was the hour before the dawn, and the sap-scent of the leaves in his uncle's garden came to him on the dew-damp breeze. His uncle walked alone down the street, a crumpled piece of paper in his hand. Olvir's hands were sore from the digging. The earth was over his head, and still they dug deeper, the shovels biting into the hard clay almost all of the way down to bedrock. He stood back from the edge of the hole, and the sap-scent of the garden was burned away by the sour smell of the lime.

The empty bags lay by the side of the grave, and his hands were blistered now as they shovelled dark earth back into the hole.

Olvir stood alone in the corridor. In his mind, he was somewhere else.

Valgard had done as he was told because he knew that, when it came down to it, Eirak's hold over the Vanir was unbreakable. He could grouse about it as he and Sigurd rode the freight elevator to the receiving platform against the liner's side, but he couldn't do anything.

Sigurd listened, but he wasn't over-sympathetic.

'And what did Eirak say?'

'He didn't want to know. He was more concerned about the effect on the rosters.'

There were a couple of Lazars waiting when the two Vanir reached the platform. They were standing blinded in the air--seal section that linked the Terminus to the liner, shivering and not making a sound. Valgard and Sigurd herded them into the elevator. Another Vanir work detail had already transferred most of the 'pa.s.sengers' down into the main part of the Terminus, but the drones always managed to round up a few stragglers.

'Don't cross him, Valgard,' Sigurd warned as he closed the cage door on the Lazars. He and Valgard remained on the platform as the elevator dropped away.

'He doesn't scare me,' Valgard said.

'He should. He's got too much power around here.'

'He's a glorified clerk, that's all. Anybody could do what he does.'

But Sigurd shook his head. 'One or two have tried, and it's not so easy. Without Eirak, the Terminus won't work.'

'That would be the company's problem,' Valgard said, but even to him it sounded hollow.

An indicator light over the elevator control came on; the cage had been emptied down below. Sigurd threw the switch for its return, and said, 'I'll tell you what the company would do. They'd starve us out and then find some other prison willing to sell off its hard cases as forced labour. Face it, Valgard, we just don't count.'

And the galling part about it was, as Valgard knew, that Sigurd was right. Terminus Incorporated had wanted a low-cost, trouble-free workforce, and they had it in the corps they called the Vanir. The rules were simple; work or die. And the means of control was the drug that they called Hydromel.

Valgard said, 'So Bor dies,' and Sigurd shrugged.

'We're all dying here anyway,' he said. 'Bor just took the easy way out.'

'That's what Eirak told me.'

'Well, he knows what he's talking about. Come on.'