'Down into the caves, it's our only chance.

'What about the Doctor?' cried Nyssa.

'Done for. Come on!'

'Wait!' shouted Tegan, pointing. The side of the Adamantium Adamantium closest to the ground was torn wide open and the ship's guts were hanging out: loose cabling and chunks of smouldering machinery. Flames were bleeding from the wound, but there was something moving through the smoke: a pale figure stumbling beneath a heavy burden. closest to the ground was torn wide open and the ship's guts were hanging out: loose cabling and chunks of smouldering machinery. Flames were bleeding from the wound, but there was something moving through the smoke: a pale figure stumbling beneath a heavy burden.

'I don't believe it,' said Stoker.

The Doctor came running, crouched low, a figure hanging limply over his shoulders. Through clenched teeth, he yelled at them all to get down.

Just as he threw Silas Cadwell's body to the ground, the Adamantium Adamantium finally blew up with a ma.s.sive, deafening howl of protest. Bright yellow fire leapt for the night sky, trailing debris. A wave of hot, pressurised air scalded them where they lay, face down in the dust. finally blew up with a ma.s.sive, deafening howl of protest. Bright yellow fire leapt for the night sky, trailing debris. A wave of hot, pressurised air scalded them where they lay, face down in the dust.

'Sorry about that,' panted the Doctor as the noise of the explosion died away. 'Took a bit longer than I intended.'

'It's time we pooled our resources,' the Doctor told Silas Cadwell a little later. They were in the main cavern again: Cadwell was sitting sullenly against the rock wall while the Doctor paced back and forth.

Cadwell was nursing an ugly head wound. The pad of material he was using to staunch the flow of blood was entirely red. 'Don't be ridiculous,' he said faintly.

'We haven't any choice,' said the Doctor.

'That's what I mean,' Cadwell replied. He dabbed at the cut on his scalp and winced. The Dark's going to kill us: we don't have any choice in the matter.'

The Doctor turned abruptly on his heel, hands deep in his trouser pockets. 'I'm sure your ancestors would be proud of you. They fought the Dark for centuries, so you said.'

'We haven't got centuries. If we're lucky, we've only a few hours.'

'Lucky?'

'I'm trapped here with the Dark,' Cadwell explained carefully, as if the Doctor was stupid. 'Death can't come soon enough.'

'Now you're just being melodramatic.'

'Don't try and goad me into helping you, Doctor,' Cadwell said. 'I refuse to give up hope.'

'You're pathetic.'

'At least I'm prepared to do something.'

'Oh, don't get me wrong: I fully intend to do do something: Cadwell tossed the blood-soaked bandage away and smiled at the Doctor. 'I'll blow my own brains out before I let the Dark get to me. I could have died quite happily on the something: Cadwell tossed the blood-soaked bandage away and smiled at the Doctor. 'I'll blow my own brains out before I let the Dark get to me. I could have died quite happily on the Adamantium, Adamantium, if it hadn't been for you. Once again, your s.p.a.ce Cadet heroics have only made matters worse.' if it hadn't been for you. Once again, your s.p.a.ce Cadet heroics have only made matters worse.'

The Doctor squatted down in front of him. 'I need your help, Cadwell. I don't want Tegan and Nyssa involved in this.'

'They already are, you fool.' Cadwell shook his head sadly. 'If I were you, I'd put a bullet through their heads before the Dark catches them: it's by far the kindest thing to do.'

The Doctor stood up with a hiss of exasperation. 'All right, Cadwell. If you won't help me, I'll do it myself.'

Cadwell lay back against the rock wall and gazed mockingly at the Doctor. 'What are you planning?'

For a long time the Doctor said nothing. Then, taking a deep breath, he said, 'Tegan and Nyssa are helping Stoker search the Adamantium Adamantium wreckage for a zenesium flare.' wreckage for a zenesium flare.'

'A zenesium flare?'

'Incredibly powerful light source, used as a beacon during planetary surveys.'

'Yes, I know what it is!'

The Doctor looked intently at Cadwell. 'If I can detonate one close enough to the Dark, there might be enough light energy to... to...'

'To what, what, exactly?' exactly?'

'Well, I'm not sure: destroy it, hopefully. Stun it, even.

Something.

Anything.'

'That's pretty desperate!'

'It's all I've got!' the Doctor thundered. 'Have you a better idea, Mr Cadwell, because if you have then I'd be very glad to hear it!'

Cadwell simply looked at the Doctor as if he was insane.

At the very least,' the Doctor added quietly, 'it's something to do while I'm waiting for the Dark to come and destroy us all.'

'What's the Doctor up to?' Tegan asked. 'Why does he want this flare thing anyway?'

Tegan, Nyssa and Stoker were working their way through the wreckage of the Adamantium. Adamantium. The fires had all but died out now, and the ship's smouldering remains appeared to have settled. A good part of the starboard side of the ship was still intact and undamaged by the fire. It was in this section of the ship that the practical survey equipment had been stored. The fires had all but died out now, and the ship's smouldering remains appeared to have settled. A good part of the starboard side of the ship was still intact and undamaged by the fire. It was in this section of the ship that the practical survey equipment had been stored.

'I suppose he thinks it might be useful against the Dark,'

Nyssa said 'He must be working on the theory that it will avoid light, or perhaps even find it harmful.'

'Sounds pretty desperate if you ask me,' Stoker muttered, ducking beneath a partially collapsed section of the corridor ceiling.

Every so often the ship would give out a metallic groan or a series of heavy, distant clangs as it settled; as far as they could tell it was reasonably safe for the moment but Tegan found the trip very unnerving. She expressed this feeling via a stream of constant complaints.

'We've got to try something,' Nyssa argued. 'We can't run away from the Dark. We can't reason with it. We have to stand and fight.'

'But it's going to be like standing and fighting an elephant with a peashooter!'

'What's a peashooter?'

'It's a small tube kids use to blow peas out of.'

'Peas?'

'Yeah. Little round vegetables. About this big.'

'I see,' Nyssa said. 'What's an elephant?'

'Oh, never mind!'

The Doctor threw down the comlink in disgust. 'Antiquated junk!'

'That's Consortium property,' Cadwell warned. 'You break it, you pay for it.'

'I'm trying to get in touch with Nyssa and Tegan: they're taking too long.'

'What's the hurry?'

The Doctor was still pacing up and down the cave. He stopped and glowered at Cadwell. 'Look around you?'

Cadwell looked around him. 'What?'

'What can you see?'

'The cave. Some of Stoker's c.r.a.ppy equipment. You. Not much else.'

'Why not much else?'

Cadwell shrugged. 'It's too dark.'

The Doctor nodded slowly. 'And it's getting darker. It has been getting darker ever since we came down here.'

Cadwell sat up, suddenly tense.

The Doctor squatted down close to him again. 'When the Adamantium Adamantium crash landed, the impact fractured the door seal in the laboratory complex. There was a fractional gap. It was still very bright in the lab itself, and I think that held it at bay for a little while, but the Dark started to seep through. Even now it's forcing its way out of the catacombs, into the lab complex. And then up here, into the caverns. It's gathering up here, preparing to strike. That's why it's getting darker. crash landed, the impact fractured the door seal in the laboratory complex. There was a fractional gap. It was still very bright in the lab itself, and I think that held it at bay for a little while, but the Dark started to seep through. Even now it's forcing its way out of the catacombs, into the lab complex. And then up here, into the caverns. It's gathering up here, preparing to strike. That's why it's getting darker.

It's coming for us.'

'Here's the stores section,' said Stoker. The deck was twisted out of shape, and it was difficult to stand upright. She edged forward and shone her torch through the buckled doorway: the door itself was a bent piece of metal tying on the floor.

'There's a fair bit of stuff in here: s.p.a.ce suits, survival equipment, portable sensor suites. All the latest mod cons.

The Consortium always had good kit.'

She climbed through the doorway and the deck immediately groaned.

'Look out!' Tegan cried, clutching at the corridor wall.

Something clanged deeper inside the wreck, a sonorous tolling that rattled everyone's nerves.

'I think this might be riskier than we first thought,'

admitted Stoker.

She moved forward and the deck complained loudly once more.

'Be careful,' said Nyssa.

'I'm OK.' Stoker shone the torch around the storeroom. 'I think the zenesium flares are over here.'

'Can you reach them?'

'I'll try: it looks like part of the wall's gone, though... it's smashed the lockers wide open.'

'Is it safe?' Tegan pointed her own torch through the doorway. 'I can't see much.

Stoker slowly knelt down. 'Some of the flares have been crushed. But there's one here which still looks functional.'

She leant forward to pick it up and the whole deck suddenly tilted. 'Whoa!'

'Keep still!' Nyssa instructed. It was then that they all heard the comlink bleep again. Nyssa pulled the handset from her trouser pocket. 'Doctor? Is that you?'

There was a crackle from the device followed by the Doctor's voice, small and tinny: ...terference. We haven't...

deal of time... etting dark...'

'You're breaking up,' Nyssa informed him.

'Can't hear... very well' the Doctor replied. 'You're breaking...' Tegan leant over and took the mike. 'Doctor!

We've found the flares! We'll be right back!'

More crackling.' ...you, Tegan? There's no need to shout: 'Tell him I've got it,' Stoker called.' and then she screamed.

Part of the deck had suddenly given way, falling through with a shriek of torn metal. Stoker hurled herself forward, scrabbling for the door. Tegan grabbed her and pulled her to safety as the whole storeroom caved in behind her.

'The flare!' cried Stoker.

'I've got it!' Nyssa said, leaning into the jagged black hole. 'It's just here...'

The ship lurched and Nyssa pitched forward into the empty s.p.a.ce. As she fell, she flung the zenesium canister back into the corridor. 'Nyssa!'