By the time Sergeant Cameron reached the bottom of the ladder that led to the top deck of the spaceship, he found he was leading his four companions.

“Ow! Stop that!” a voice cried from behind.

A clattering sound followed. Cameron stopped with one hand on the ladder and looked back as Private Wells and Private Ellison caught up.

“What’s going on, Doctor?” Cameron called.

The Doctor was rubbing his palms together and grimacing, about twenty yards behind. Rose was standing near him, her hands on her hips.

“It keeps on giving me electric shocks!” the Doctor cried.

The War Brain, which Cameron noticed was lying on its side at the Doctor’s feet, let out another unsettlingly inhuman chortle.

“We don’t have time for this,” Cameron said impatiently.

“It knows that, Sergeant,” the Doctor growled.

Cameron sighed, then looked at Wells and Ellison. Neither of their wounds were as superficial as their battle-ready postures seemed to suggest, but at least they had both realised their pain response was simply a pre-programmed protocol.

“Okay, we’re at the top of the ship now,” he told them. “The Doc says all the Cybermen will be up here. We’re all armed, as good as they are, but there’s more of them. Don’t bunch up and get cornered, but don’t get spread too thin.”

Wells and Ellison nodded their understanding.

Cameron glanced back at the Doctor, who was now struggling to pick the War Brain up with his jacketed forearms instead of his bare hands.

Suddenly, the omnipresent humming that was warbling through the ship began to fall in pitch, until it was too low to hear. The five of them stopped.

“We’re slowing down,” Ellison murmured.

Then the ship gave a little jolt, not as violent as the shaking they’d felt as the ship hurtled through the planet’s atmosphere, but still noticeable.

The Doctor finally caught up, lips pressed together so tightly they were white.

“We better hurry,” said Rose.

“We just docked,” the Doctor explained.

Rose was the last one up the ladder. She heard the distant sound of gunfire as she climbed, but it wasn’t Sergeant Cameron and his men. The sound was of machine gun fire, several machine guns, being fired continuously. But by the time she got to her feet at the top of the ladder, there was nothing but silence.

Then the Doctor yelped loudly and dropped the War Brain again.

“You’re too late, Doctor,” it said.

Cameron, Wells and Ellison were creeping round the next corner. Cameron turned back and gave the Doctor and Rose the all-clear signal.

The Doctor went to pick the War Brain up.

Rose saw the crackle of static current it was preparing in advance and put a hand on the Doctor’s arm. “I’ve got a better idea, Doctor.”

“You’re a little thug,” said the War Brain.

Then Rose gave it a hard kick with the side of her foot. The War Brain rolled over three or four times then skidded another couple of yards.

The Doctor roared with laughter. “Genius!”

Rose and the Doctor took turns kicking the War Brain along the passage, and soon they reached the corner. Cameron and the others were already waiting at the next. The sergeant gave them another hand signal, then went into the next corridor.

“They’re all on the station, aren’t they?” Rose said.

“There’s still time,” the Doctor muttered.

The War Brain started to laugh again, and this time it didn’t stop.

The Doctor quite enjoyed kicking the War Brain, even though he doubted they were causing it any damage. It was going to take a force a lot stronger than it took to score a penalty to just break through the Thrukstone machine’s outer casing.

Still, it was a lot quicker to kick it than to carry it.

They finally caught up with Sergeant Cameron and his men on the other side of a perfectly square opening. Disorientated, it took the Doctor a second to realise it was the airlock they had entered the spaceship by. The last time he had seen it there was a ‘giant snake’ on the other side. Now there was a space-station.

And about a dozen human corpses.

“Oh my god,” said Rose, putting a hand to her mouth.

The bodies, most of them lying face down, were dressed in identical black one-piece battle-suits, with contoured armour plating. They all wore tight-fit helmets, and some of them were still clinging onto their machine guns.

“Looks like a security team,” said the Doctor.

Cameron and Private Wells were moving along the docking channel that led from the airlock to the rest of the space-station, checking bodies as they went. Private Ellison was already at the far end, kneeling in the firing position.

“They didn’t stand a chance,” Wells hissed.

“Of course not,” said Cameron. “They were completely unprepared.”

Some of the bodies still had pulse-gun burns that were smouldering.

Suddenly, there was the sound of distant gunfire again. They all stopped what they were doing and listened. Cameron and Wells dropped the floppy wrists they were lifting up. The Doctor felt Rose grab his right hand.

Somewhere deeper in the station, passages and maybe even decks away, a new battle was being fought. Like the last one, it was over quickly.

“All right, let’s go,” Cameron decided.

He and Wells began picking their way around the bodies.

The Doctor rolled the War Brain over the lip where the space-station met the spaceship with his foot, then looked around at Rose.

“Come on,” he said softly. “It’s okay.”

Then he pulled on her hand, and guided her gently over the threshold.

He had to carry the War Brain over the dead bodies, and it didn’t shock him once. He knew that its sudden relative helpfulness was a cause for concern, but he was just grateful to be able to keep up with the others for once.

“Doctor, look at this,” Cameron said as he and Rose caught up.

Cameron had stopped at the end of the docking channel and was looking at a level plan on the wall. It was a far more detailed map of the station than any of the level plans that had got the Doctor separated from the Tardis to begin with.

“The Cybermen will be heading to the command centre,” he said. “Everything they want from this station they can get from there.”

Cameron quickly located it. “Okay, but where are we?”

“Here,” said the Doctor, pointing, then tracing a route between.

“That’s a long way. This could work in our favour.”

The Doctor nodded. “They will have seen this map, Sergeant. They know the most direct route and they’ll be following it. You won’t be able to beat them there, but you should be able to catch up with them before they get there; if you hurry.”

By way of reward for daring to pick it up again, the War Brain decided now would be a good time to give the Doctor another shock.

The Doctor dropped it forcefully. It appeared to bounce.

“Doctor, let one of us carry that,” Cameron said quietly. “We can’t keep stopping like this every time you drop the thing.”

The Doctor shook his head vehemently. “I’m not going to burden one of your men with this thing. You need all the trained soldiers we’ve got.”

“No, Doctor. I need more.” He smiled.

“Precisely, and you need them carrying guns, Sergeant, not computers. You go ahead, and Rose and I will follow you as fast as we can.”

Cameron sighed. “You sure, Doctor?”

“You’ll be between us and the Cybermen,” Rose added. “We’ll be okay.”

Cameron tapped a few fingers to his forehead in genial salute.

“Good luck,” the Doctor said.

“Not that luck thing again,” Cameron growled.

“As a man of science,” the Doctor pontificated, hands in pockets. “And given what I’ve been through today, I think there’s a lot to be said for the concept of luck.”

“Then I hope it’s still on our side.”

Somewhere on the station, gunfire erupted once more.

“Sarge, come on!” Ellison said.

Cameron started walking backward. “See you in Berlin, Doctor.”

Then he disappeared around the next corner with Wells and Ellison. Rose and the Doctor listened to them disappear into the distance. Around the same time, the far away machine gun fire also died down. The Cybermen had won another battle.

“You’ll never see them again, Doctor,” the War Brain said.

Rose snorted. “You wish, bolt-bucket.”

Then she gave it an almighty kick and it shot off down the passage.

The Cybermen reached a wide, two-tiered arcade. It went round in a curve, so that they couldn’t see the far end. The Cyberleader’s enhanced brain remembered the level plan from the docking channel as perfectly as if it had photographed it. This part of the station was right next to the hull. They had to follow the arcade for just under three hundred yards, then take an emergency stairwell to the next deck up.

The Cybermen walked in single file, their pulse-guns held across their chest in anticipation of resistance. They didn’t get far before that resistance appeared.

A walkway ran along the upper tier. There were closed doors and shuttered windows on one side, and an opaque safety barrier on the other. Its brain attuned to battle, the Cyberleader recognised a vantage point when it saw one.

Sure enough, as the Cybermen walked beneath a particular section of the walkway, the barrels of a dozen machine guns appeared over the top. There were men hiding behind the barrier, firing blind on the Cybermen.

“Concussion frag,” the Cyberleader said.

In unintentional unison, the ten Cybermen in the group snapped the ends of their pulse-guns into the concussion frag position and aimed high.

The rounds they fired shot into the air like flares, and like flares drifted down behind the barrier. There was an intense white light and a hiss as they exploded.

Screaming, a dozen humans poured over the barrier.

“Standard fire,” the Cyberleader said.

The ten Cybermen adjusted their pulse-guns back again.

Some of the humans were already dead; the fall had killed them. Others were convulsing, their eyes swollen and bleeding as they clawed at the deck, as if struck by nerve gas. A volley of Cyberman fire later and they were all dead.

The ten Cybermen stepped over them, and continued along the arcade.

“I won’t shock you, Doctor,” the War Brain said.

Rose and the Doctor were standing at the bottom of a stairwell that Sergeant Cameron and his men had used perhaps a minute before them. Rose spotted droplets of black android blood on several of the steps.

“Is that a promise or a prediction?” the Doctor asked.

“Which would you believe more?”

The Doctor gave a snide laugh and turned to Rose. “Go and stand at the top and keep that door from closing; I’m going to throw it.”

Rose nodded and ran up the stairs. The automatic door at the top swished open, and she stood next to it so that it would stay that way.

In one swift move, the Doctor scooped the War Brain up; it gave him a shock, but he was already pitching it over his shoulder. He launched it up the stairs and it landed on the top step, where Rose kicked it through the open door.

The Doctor danced up the stairs, three at a time.

“This way,” he said, not stopping.

Rose and the Doctor kicked the War Brain to the next junction, where the Doctor stopped briefly to check the level plan.

“Turn right,” said the War Brain.

The Doctor turned left. The spots of android blood were further apart here; the marines must have been running, thought Rose.

Somewhere above them, another fierce gun battle was being fought. It was just as brief as the previous ones. Rose feared for Cameron and the others.

They quickly reached yet another junction.

“This way,” said the Doctor, barely stopping to check the level plan.

Behind him, Rose kicked the War Brain hard, so that it would hit the far wall and rebound around the corner. Then she started dribbling it.

“Show off,” said the War Brain.

Rose grinned. It wasn’t until they reached the next four-way intersection that she realised she hadn’t seen any black droplets since the last one.

“This way,” the Doctor said without slowing.

Rose stopped at the level plan on the wall. She frowned. She couldn’t see the Operations Centre marked on the map at all, whereas at all the previous junctions it had been right at the top. She called out to the Doctor.

“We don’t have time for this,” he warned her, cocking a thumb.

“Doctor, I think we’ve taken a wrong turning.”

“We haven’t. Trust me, Rose.” He gave her a sincere look.

She shook her head. “The command centre isn’t even on this map!”

Sitting at her feet, the War Brain began to laugh.

“He isn’t following Sergeant Cameron, Rose,” it said.

Rose frowned at the Doctor. “What?”

“He has no intention of going to help them.”

“Doctor, it’s lying again, isn’t it?”

The Doctor sighed. “Rose, I told you down on the planet that the most important thing was that the Cybermen didn’t get their hands on the War Brain. That hasn’t changed. In fact, it’s even more important now.”

“He’s going back to the Tardis,” the War Brain added.

“We’re running away?” Rose cried.

“As soon as we’re inside the Tardis I can take this thing a million miles and a billion years away from the nearest Cyberman, Rose.”

“What will happen to Sergeant Cameron and the others?”

“They all die horribly,” the War Brain said.

“Don’t listen to it, Rose,” the Doctor said. “It wants to stay on the station, so it needs us to stay here too. Cameron and his men have proved themselves more than adept at dealing with Cybermen. What help could we give them?”

Rose chewed her bottom lip. “I suppose.”

“You should see how Private Ellison dies,” the War Brain said.

I am ignoring it, Rose told herself. This is me ignoring the War Brain.

“There’s a freight elevator here,” the Doctor said, pointing on the map. “With any luck it will take us right down to level 38, where the Tardis is.”

Rose took a deep breath. “Okay; let’s go.”

As they ran, the Doctor had to listen to the War Brain’s ever more elaborate, ever more horrific descriptions of how Sergeant Cameron and Private Ellison and Private Wells would meet their ends. He glanced across at Rose, but her expression was fixed and determined, as if she was trying to ignore what it said.

The Doctor could tell that she was hearing every word. Each time she kicked the War Brain she kicked it a little harder, and the Doctor had to run a little further before it was his turn to kick it. In fact, the last time she kicked it, she kicked it right past the freight elevator, and he had to chase after it to bring it back.

“It goes to alternate floors,” the Doctor said, reading the panel beside the door after he’d pressed the round button to call the elevator.

“What use it that?” said Rose.

“There’s probably another elevator that stops at the others.”

The War Brain began to cackle again.

“Oh, give it a rest,” Rose said under her breath.

“There are Cybermen on level 38, Doctor,” the War Brain said.

The Doctor sniffed. “This is level 12. Level 38 is down. The command centre is on level 1, which is up. All the Cybermen are going there.”

Just then the doors opened. Rose went in. The Doctor kicked the War Brain in after her. It was a large elevator, big enough for a vehicle, but it was empty.

The War Brain laughed again. “On the contrary, Doctor. On level 40 there is a nuclear fusion reactor. Twelve Cybermen are currently on their way to secure it in case the humans decide to blow up the station.”

“It could be telling the truth, Doctor,” Rose said.

“That’d make a change,” he said.

Then he pressed the button for level 38.

Sergeant Cameron and his men ran onto the arcade. There were the corpses of another security team everywhere. The trail of dead the Cybermen left behind them no longer fazed Cameron for what it was. Indeed, as they stepped over the bodies, he looked to them as a positive sign that the trio of marines was on the right track.

“Sarge; wait, I think I can hear something,” said Private Wells.

Cameron and Private Ellison stopped and turned.

“There it was again,” said Wells.

“I didn’t hear anything,” Ellison snapped.

“What was it, Wells?” Cameron asked.

“Sounded like a voice,” Wells replied. “There!”

Cameron couldn’t hear anything. Then he looked where Wells was standing; bringing up the rear, he was the closest to the fallen security team.

“There it is again,” Wells hissed. He looked around, and seemed to settle on the nearest security team member at the same time Cameron did.

The dead human was lying at a strange angle, his neck clearly broken. His helmet was half hanging off his head. Cameron saw a microphone inside.

“There’s a radio in his helmet!” he hissed.

Wells bent down and pulled the helmet off the man’s head. He looked inside and nodded to Cameron. Cameron went and snatched it off him.

It was a tight fit, but he managed to pull it on.

“Hello?” he went. “Hello?”

A digitised voice crackled in both ears. “Who’s this? McReady, is that you?”

“No, this is Sergeant Cameron.”

A pause. “Who?”

“Look, it doesn’t matter. Are you in the Operations Centre?”

“Yes. Who are you?”

Cameron sighed. “Listen to me: you’ve got to pull your men back. They’re getting wiped out down here. Pull them back to Ops. Do you hear?”

“What’s your clearance ID?”

“Goddamn it, man! These things are coming right for you. They’re killing everyone in their way. Pull your men back! You’ve got to build a strong line of defence around Ops. Concentrate your forces there. It’s your only chance!”

“Identify yourself. Immediately.”

“Sergeant Cameron. I’m from the SS Reliant.”

Another voice came over the headphones: “This is Commandant Fletcher speaking. Who did you say you were?”

The elevator doors opened and Rose kicked the War Brain out.

“Can’t be far now,” the Doctor said cheerfully.

“Which way is it?” Rose asked.

The Doctor frowned. “I don’t know. This is how we got lost last time.”

“I thought you said that was having fun exploring.” She smiled.

“Yes, but there’s only so much fun you can have.” He walked up to the nearest door then came back again, shaking his head.

“Ask that thing,” Rose said, cocking her head.

“No. It always lies.”

Rose frowned. She suddenly had an idea.

“Hey, Brain,” she said, squatting down. “You know those Cybermen you said were down here; which way are they?”

“Left,” it replied.

Rose leapt up. “Doctor, we go left.”

The Doctor looked impressed. “Why didn’t I think of that?”

Rose and the Doctor headed left from the freight elevator, and kicked the War Brain about seventy yards to a T-junction. The Doctor looked ecstatic to find a bay door that said C38, and another thirty yards along, one that said C38-Beta.

“I hope these are in sequence!” he sang.

Rose found herself kicking the War Brain all by herself as the Doctor ran ahead. Before they reached the next corner, they had passed both D38, and D38-Beta.

“You’re going to die, Rose,” the War Brain said.

But Rose ignored it as she followed the Doctor round the corner. There were two doors along this corridor. The Doctor whooped when he reached the first.

“E38!” He waited for Rose and spun her around.

“It’s the next one?” she said.

The Doctor grinned, and bounded off.

“Finally,” said Rose, glancing at her watch. It had been almost a full twenty-four hours since she and the Doctor had last walked down here.

She recognised the dull thuds instantly.

They were coming from beyond the next corner. The next door - the door the Doctor expected to be E38-Beta - was right on that corner.

The Doctor stopped before he reached it. “What’s that noise?”

The heavy metal footsteps came closer.

“I told you the Cybermen were left, Rose,” said the War Brain. “Did you think I didn’t know you were going to second-guess me?”

“Doctor, run!” Rose shouted.

As the Cybermen came marching round the corner, instantly blocking the way to E38-Beta, the War Brain began to laugh and laugh and laugh.

NOTES:
Not my favourite chapter. I didn't intend for it to be another 3500 words of chasing around corridors. I threw in the bit from the Cybermen's perspective during the arcade assault just to break things up a bit. It seemed like cheating to keep describing battles from the perspective of people who can only hear them from a distance, and then have them happen on piles of bodies repeatedly. The next chapter is the all-action part of the finale (another three chapters are presently anticipated), for which this one was largely about joining the part of the story that happens on Erebus to the part of the story that takes place on the Titan Orbital.