What would happen if it turned out Rose's presence in the parallel world caused a misbalance?

(No Martha or Jones family in this one)

Chapter 10: The Sound of Drums

The Doctor, Dani and Jack all dropped into an alleyway and groaned, except Jack who was more accustomed to the pain.

'Time travel without a capsule,' the Doctor mused. 'That's a killer.' He cracked his neck. Dani yanked one of the "vote Saxon" posters from the wall behind her. She whacked it with the back of her fingers. 'I knew I'd seen that face somewhere before!'

The Doctor came over and took the poster from her. 'Saxon? A politician?'

'I think so, yeah,' Dani said. 'We'll know for sure if we find one of those billboards with his face pasted all over it.'

'Let's go,' the Doctor said, leading them out of the alley.

They were walking down the street when Jack made the remark, 'Still, at least we made it. Earth, 21st century by the looks of it. Talk about lucky.'

'That wasn't luck,' the Doctor said. 'That was me.'

They all sat down.

'The moral is, if you're gonna get stuck at the end of the universe, get stuck with an ex-Time Agent and his vortex manipulator,' Jack said.

'The Master's got the TARDIS,' Dani said. 'And there's a high chance, he's the next Prime Minister.' She looked at the Doctor. 'Is he even here?'

'No, he's here,' the Doctor said. 'Trust me.'

'He must have regenerated,' Dani said. 'His voice was different at the end.'

'So how are we gonna find him?' Jack asked. 'We have no idea what he looks like.'

'I'll know him,' the Doctor told them. 'Moment I see him. Time Lords always do.' He looked at Dani. 'You saw him?'

'Before he sent out some sort of pulse and blew me out of the TARDIS and into you two, yeah,' she answered. 'I didn't see much of him. I jumped on his back and only really saw his hair. It was short and brown. Not as short as yours was last life, but close. And he was really skinny too. Doesn't really narrow it down, though. If he's not Saxon, he could be anyone.'

'Mr. Saxon is returning from the palace and is greeting the crowd inside Saxon headquarters,' the news reporter on the TV behind them said.

They turned to see if it was the Master.

'That's him,' the Doctor said. 'He's Prime Minister. Dani, you were right. The Master is Prime Minister of Great Britain. The Master and his wife?'

'See, now that's creepy,' Dani said.

The Master stepped forward and began a speech. 'This country has been sick. This country needs healing. This country needs medicine. In fact, I'd go so far as to say, that what this country really needs right now is a Doctor.'

Dani cringed. 'And that's just nasty.'

XXX

Carly turned around from where she was pulling the first fraction of the paradox machine apart. Her jacket was thrown over one of the coral-like struts surrounding the outer console room. She knew what Saxon had just said.

'Great pun, mate,' she muttered. 'What next, you bleeding ponce?'

She checked on Rose as she continued work.

XXX

Dani led them into her flat.

'What have you got?' the Doctor asked. 'Computer? Laptop? Anything.' He looked at Jack. 'Who are you phoning? You're not telling anyone we're here.'

'Just some friends of mine,' Jack said. 'But they're not picking up.'

Dani pulled out her laptop and handed it to the Doctor.

'Sorry,' Dani said. 'In here, I've only got human stuff. All the alien stuff's at the Kaias HQ.'

'I can show you the Saxon websites.' Jack took the laptop. 'He's been around for ages.'

'Wait,' Dani said. 'I'm just gonna send out Kaias protocol 2.'

'What's that?' the Doctor asked as she sent it out.

'Bio-scan on the Prime Minister,' Dani answered. 'It's a Handiconean one. Can do it from a distance and gives us everything. Internal workings, race and genetic code. It's basically my way of telling them that Harold Saxon is the Master. I thought there was a possibility the Master may come back so I had his genetic code loaded into the Kaias databanks.'

The Doctor grinned. 'That's my girl.'

'Here we go,' Jack said.

They played a few videos that basically publicised that Harold Saxon should be voted for no matter what. He was great and awesome and whatever else humans thought meant positive.

'Former Minister of Defence,' Jack read. 'First came to prominence when he shot down the Racnoss on Christmas Eve.' He turned around. 'Nice work, by the way,' he told the Doctor.

'Oh, thanks,' the Doctor responded.

'But he goes back years,' Dani muttered, coming over. 'He's famous. Everyone knows his story. How did he do that? I mean, look. Cambridge University, Rugby blue, won the athletics, wrote a novel, went into business, got married and everything like that.' She cocked her head. 'Unless…' She turned to face the Doctor. 'Do you reckon he faked everything?'

'That's the only thing that makes sense,' the Doctor said.

XXX

Carly froze. A Toclafane was killing a human. And she'd interrupted the paradox machine, so some Toclafane were bound to vanish. Carly pulled herself out from under the console and replaced the hatch. Then she grabbed her jacket from the captain's chair as she ran past. It didn't take long for the Master to come, via teleport.

Carly knew the mind of a Time Lord was by far more difficult to manipulate than the mind of a human was. A human couldn't detect you. A Time Lord could. If you didn't do it fast enough. She waited until she heard the door open and then shot the assumption through his head. She held her breath and waited.

'Oh,' the Master muttered. 'Did I leave that? Well! Even I must slip at times.'

She kept her sigh of relief as quiet as was physically possible.

XXX

'But he's got the TARDIS.' Jack pointed out from where he was making the three of them tea. 'Maybe the Master went back in time and has been living here for decades.'

'No,' the Doctor said, still surfing the Saxon site.

'Why not?' Jack asked. 'Worked for me.'

He gave Dani and the Doctor their mugs of tea.

'When he was stealing the TARDIS the only thing I could do was fuse the coordinates,' the Doctor answered. 'I locked them permanently.'

'Until you can get to it,' Dani said.

'Yeah,' he said. 'He can only travel between the year 100 trillion and the last place the TARDIS landed. Which is right here, right now. So Dani's theory is far more likely.'

'Yeah,' Jack shook his head. 'But a little leeway?'

'Well, 18 months, tops,' the Doctor allowed. 'The most he could have been here is 18 months. So how's he managed all this?'

'18 months?' Dani asked.

'Yeah,' the Doctor agreed. 'Does that mean something to you?'

'18 months.' Dani nodded. 'I think I just figured out how he did it.'

'What do you mean?' Jack asked.

'The Master was always sort of hypnotic, but this is on a massive scale,' the Doctor said. 'You think you figured out how he did it?'

'Before I headed up the Kaias Foundation, I had no need for a mobile phone, so I didn't own one,' she explained. 'But about 16 months ago the Kaias came together properly. We needed to camouflage and mobile phones were part of that. That was the first time I picked up a mobile. And everytime I spoke on it, I heard something. A rhythm. And I wasn't the only one. Anyone in Kaias with acute hearing could hear it. We assumed it was something that was on the back of every mobile, undetectable to human senses and it just became a nuisance. But, now that I think about it, I realise that every single person who can hear it finds Saxon the same kind of nuisance.'

The Doctor considered this. 'What does it sound like?'

Dani leant on the bench she was next to and started repetitively knocking a rhythm of four out onto it. She stopped as a broadcast from Saxon came on.

XXX

Carly was dismantling the paradox machine again.

'That's gonna go over like a lead salami,' she remarked. 'Apart from the humans, that is. But it will help me for the next few hours.' She smirked up into the innards of the machine. 'Thanks, Harold Saxon.'

XXX

'Every man, woman and child, every teacher and chemist and lorry driver and farmer and oh, I don't know, every…reformed fugitive?'

The Doctor and Jack twisted around and looked at Dani.

'Oh…damn,' Dani said.

The Doctor twisted the TV around and found a ticking bomb strapped to the back. They had seconds to get out.

'Out!' the Doctor yelled.

They all bolted out. The Doctor grabbed the laptop and his coat. They ran out of the flat building and into the street. The flat exploded, taking four other flats with it. Dani brushed her hair back.

'S-O-B,' she said. Dani's phone rang. 'Hello?' She paused. 'You killed five people, Master.'

The Doctor came over and she handed over the phone. 'I'm here.'

'Doctor,' the Master said.

'Master,' the Doctor responded.

'I like it when you use my name,' the Master told him.

'You chose it,' the Doctor said. 'Psychiatrist's field day.'

'As you chose yours,' the Master agreed. 'The man who makes people better. How sanctimonious is that?'

'So, Prime Minister, then?' the Doctor asked. 'Subliminal messages?'

'How'd you know?' the Master murmured.

'Dani,' the Doctor answered. 'You should know, Master. One of the Presan fugitives. Prepared for every eventuality. Even unnatural ones. She heard it, loud and clear. Who were those creatures? There's no such thing as the Toclafane. That's just a made-up name like the boogieman.'

'Do you remember all those fairytales about the Toclafane when we were kids?' the Master asked. 'Back home? Where is it, Doctor?'

'Gone,' the Doctor answered.

'How can Gallifrey be gone?' the Master asked.

'It burnt,' the Doctor said.

'And the Time Lords?' the Master asked.

'Dead,' the Doctor answered. 'And the Daleks. More or less. What happened to you?'

'The Time Lords only resurrected me because they knew I'd be the perfect warrior for a Time War,' the Master answered. 'I was there when the Dalek Emperor took control of the Cruciform. I saw it. I ran. I ran so far. Made myself human so they would never find me, because…I was so scared.'

'I know.' The Doctor remembered the fear.

'All of them?' the Master asked. 'But not you. Which must mean…'

'I was the only one who could end it,' the Doctor confirmed. 'And I tried. I did. I tried everything.'

'What did it feel like, though?' the Master asked. 'Two almighty civilisations burning. Oh, tell me, how did that feel?'

'Stop it,' the Doctor told him.

'You must have been like God,' the Master mused.

'I've been alone ever since,' the Doctor answered. 'But not anymore. Don't you see all we've got is each other?'

'Are you asking me out on a date?' the Master asked.

He pretended he didn't say that. 'You could stop this right now, we could leave this planet. We can fight across the constellations if that's what you want. But not on Earth.'

'Too late,' the Master told him.

'Why do you say that?' the Doctor asked.

'The drumming,' the Master answered. 'Can't you hear it? I thought it would stop, but it never does. It never, ever stops. Inside my head. The drumming, Doctor, the constant drumming.'

'I could help you,' he said. 'Please, let me help.'

'It's everywhere,' the Master said. 'Listen, listen, listen. Here come the drums. Here come the drums.'

'What have you done?' the Doctor asked. 'Tell me. What are those creatures? Tell me!'

'Oh!' the Master exclaimed. 'Look! You're on TV!'

'Stop it,' the Doctor told him. 'Answer me.'

'No, really,' the Master told him. 'You're on telly! You and your little band.'

The Doctor looked. Nationwide terrorists. He hung up and bolted back to his companions.

'Get in the car!' he yelled. 'Get in the car!'

'Huh?' Dani asked. 'Why?'

'The Master's named us as terrorists!' the Doctor answered. 'Where can we go?'

'Kaias HQ,' Dani answered, climbing into her car behind the wheel.

The Doctor climbed in the passenger side and Jack in the back. Dani put her foot down and they shot forward.

XXX

Dani led the Doctor and Jack through the Kaias Foundation HQ. It was situated in an interesting place.

'Under the Atlantic Ocean?' the Doctor asked. 'Why have you planted a base under the Atlantic Ocean?'

'The UK and the USA have the highest percentage of alien activity in the world,' Dani answered. 'A base between the two made more sense than in one or the other. And, as for beneath the Atlantic…who's gonna suspect a base to be here? Humans don't have that technology.'

'Got a point, I suppose,' the Doctor allowed.

Dani led them into the conference room, where the four Faction Leaders were gathered.

'Conveniently, everyone knows everyone,' Dani said as she, the Doctor and Jack sat down at the table.

'Harold Saxon's the Master?' Maz asked, looking immensely confused. 'But, according to historical record, that guy was swallowed by the Eye of Harmony on the 31st of December, 1999 at 11:59pm. How is he still alive?'

'The Time Lords resurrected him for the Time War,' the Doctor answered. 'He ran away. Now he's back.'

'Don't know how they did it,' Dani griped, sitting at the head of the table with the Doctor. 'He'd used up all 13 lives. What'd they do? Renew the regenerative cycle?'

'Probably,' the Doctor said. 'We've just got to figure out what he's up to.'

'Jarvis?' Dani asked.

'Got access to the government,' Jarvis said. 'So we can track Saxon's movements.'

'Good,' Dani said.

'What do you usually do in here?' Jack asked.

'Oh, debrief,' Dani answered. 'Plan. Spy on people. Same thing you do in yours.'

'In that case.' Jack looked at the Doctor. 'So, Doctor, who is the Master?'

The Doctor looked up at Jack. Dani gave him a very light kick under the table. He'd have to tell him sometime.

'How come the ancient society of the Time Lords created a psychopath?' Jack asked.

'Tell him the other bit too,' Dani told him. 'What he was to you.'

'A friend at first,' the Doctor said.

'But all the legends of Gallifrey made it sound so perfect,' Jack said.

'Well, perfect to look at, maybe,' the Doctor agreed. 'And it was, it was beautiful. They used to call it the Shining World of the Seven Systems. And on the continent of Wild Endeavour, in the mountains of Solace and Solitude, there stood the Citadel of the Time Lords. The oldest and most mighty race in the universe, looking down on the galaxies below, sworn never to interfere. Only to watch. Children of Gallifrey, taken from their families at the age of eight to enter the Academy. And some say that's where it all began. When he was a child. That's when the Master saw eternity. As a novice, he was taken for initiation. He stood in front of the Untempered Schism, it's a gap in the fabric of reality through which could be seen the whole of the vortex. You stand there, eight-years-old, staring at the raw power of time and space. Just a child. Some would be inspired. Some would run away. And some would go mad.' He shook himself out of it. 'I don't know.'

'He ran away.' Dani told every one else at the table, pointing to the Doctor.

'I never stopped,' the Doctor agreed.

Jack's vortex manipulator beeped. Jack looked. 'Encrypted channel. With files attached.'

Dani got a slight smirk on her face.

'That's mean,' Lassa told her.

'I like seeing ego-centric people get in trouble,' Dani responded.

Jarvis gestured Jack to come over so they could access the hardware.

'Why's he getting in trouble?' the Doctor asked.

XXX

The Doctor soon found out. When he saw the Torchwood symbol. 'You work for Torchwood?' He demanded, feeling his temper flaring.

'I swear to you,' Jack said. 'It's different. It's changed. There's only half a dozen of us now.'

'Everything Torchwood did and you're part of it?' the Doctor barely let Jack finish.

'The old regime was destroyed at Canary Wharf,' Jack told him. 'I rebuilt it. I changed it. And when I did that, I did it for you. In your honour.'

The Doctor stared at him harshly.

'Dani,' Lassa begged.

Dani sighed and caught the Doctor's shoulder. 'Yeah, he did. His team doesn't even know your name, save one, and he's had it explained you're not an enemy. What happened at Canary Wharf could never happen again because they don't have an idiot in charge. Jack's probably the best human to have in charge of that lot. He's even made an easy alliance with this Foundation. I never trusted the old regime. I destroyed two of their branches prior to the Battle.'

The Doctor paused, considering that. He knew Dani was telling him the truth. He knew he should forgive Jack, but Rose's face as she looked over her father's shoulder before he teleported out flashed before the Doctor's eyes.

'Is that what happened?' Jack asked. 'Oh, you must have knocked the cliff under Torchwood 2 down then?'

'Hey, they attacked us.' Dani held up her hands.

'How'd you make Torchwood 4 disappear?' Jack asked.

'Disintegration gun,' Dani answered. 'They had no idea how to use it. Because of that aliens were losing half their bodies and dying slowly and very painfully. So I just showed them how to use it.'

The Doctor nodded to Jarvis. He hit the activation button. A woman was on the screen.

'If I haven't returned to my desk by 2200 this file will be e-mailed to Torchwood,' she said. 'Which means if you're watching this then I'm…anyway, the Saxon files are attached, but take a look at the Archangel document. That's when it all started, when Harry Saxon became Minister in charge of launching the Archangel Network.'

'What's the Archangel Network?' the Doctor asked.

'It's a mobile phone network,' Dani answered. 'Everyone on the planet's got it.'

'Yeah, it's gone worldwide,' Jack said. 'They've got 15 satellites in orbit. Even the other networks. They're all carried by Archangel.'

'Is that how the entire world got brainwashed?' Sark asked.

'Put your phones out,' the Doctor told them. 'Everyone.'

Soon six mobile phones were pushed to the Doctor. He pulled out his sonic screwdriver and soniced them all.

'Wait, wait, wait,' he said. 'Hold on.' He grabbed each phone and hit them on the table in turn. As he did, the beeping every sharp-eared alien had been hearing became audible to everyone. '"Vote Saxon. Believe in me". Whispering to the world. Any more than this rhythm and code and a strong-willed person would question it. Oh! Yes! That's how he hid himself from me!'

'How?' Jarvis asked. 'I mean, you should've sensed there was another Time Lord on Earth.'

'That's what you always told me.' Dani nodded.

'I should've known way back,' the Doctor said. 'But the signal cancelled him out.'

'Anyway you can stop him?' Jack asked.

'Not from down here,' the Doctor answered. 'But now we know for sure how he's doing it.'

'And we can fight back?' Lassa asked. 'Save all those lives?'

'Oh, yes!' the Doctor crowed.

XXX

'Three TARDIS keys.' The Doctor dropped the keys on the table. The ones he'd gotten from Dani and Jack. 'I can only use what I've got.'

'It's okay,' Lassa said. 'We've got force fields.'

'Good,' the Doctor said. 'Three pieces of the TARDIS. All with low-level perception properties because the TARDIS is designed to blend in. Well, sort of, but now, the Archangel Network's got a second low-level signal. Weld the key to the network, and Dani…' He stepped back. 'Look at me, you can see me, yes?'

'Yeah.' Dani nodded.

'What about now?' The Doctor hooked the key around his neck.

Dani's onyx eyes veered away from the Doctor. She blinked. Jack and some of her team around her chuckled.

'No,' the Doctor said. 'I'm here. Look at me.'

She tried to refocus, but it didn't work. 'Oh, I get it. I know you're there, but I don't wanna know. Tricks the perception, eh?'

'And back again.' The Doctor pulled it from around his neck.

Dani's team gave him a round of applause. He grinned and Dani put her hand over her face.

'Guys!' She groaned. 'Ego!'

'See?' the Doctor asked, giving the keys back. 'It just shifts your perception. A tiny little bit. Doesn't make us invisible. Just unnoticed. Oh, I know what it's like. It's like when you fancy someone and they don't even know you exist.'

Dani snorted in laughter. 'Don't make that comparison ever again. There might actually be someone in the room who does.'

'So you can get the TARDIS back right under the Master's nose?' Maz asked. 'That is brilliant.'

'Isn't it just?' The Doctor laughed.

XXX

They walked out of the front entrance and into the street.

'Don't run,' the Doctor told Dani and Jack. 'Don't shout, just keep your voice down. Draw attention to yourself and the spell is broken. Just keep to the shadows.'

'Like ghosts?' Jack asked.

'Yeah,' the Doctor said. They looped the keys around their necks. 'That's what we are. Ghosts.'

It worked like a charm. They walked, unnoticed through the streets of London. Ghosts of London.

XXX

They into the Master's ship, the Valiant, and got to the TARDIS. They were undetected. Almost. They got to the door and there was suddenly a transparent green bubble around them and the TARDIS. Dani went and tapped the inside of it. There was no sound and the barrier didn't ripple like force fields usually did.

'What is it?' Jack asked.

'The Impenetrable Barrier,' Dani answered. 'I've only seen it once. Once it's erected, nothing gets in or out. The harder you hit it, the bigger of a splat you make. Going slow doesn't help either. Then it's just like walking into a wall.'

The Doctor nodded in approval, having heard this before, and pulled out his sonic screwdriver. He soniced the barrier. This was the most powerful barrier he'd ever come across. And that was saying something.

'How do you get this thing up?' Jack asked. 'The last time you saw it, anyway?'

'Well only one kind of person can,' Dani said. 'And she doesn't do this very often. She prefers to be a bit more conventional. She's got two highly sophisticated guns, for the early 21st century, strapped to her hips, she can fire a bow somewhere around the level of Robin Hood, she knows every language on Earth and is trained in every form of martial arts ditto and knows everything that could possibly be crammed in a human brain.' She paused. 'There's a fair bit more room in there than I thought there was.'

'When does she usually use this?' the Doctor asked.

'Two conditions,' Dani answered. 'The first is when she has to do something and she can't have any interruptions.'

'And the second condition?' Jack asked.

'Trying to keep someone alive,' Dani said. 'Whether that be one person or a group of people, it doesn't matter. She puts the barrier up to keep someone alive. There are various reasons for that. Sometimes it's because they'll be needed in the future, sometimes it's because it's not their time and sometimes she just being sentimental.'

'It's Carly, isn't it?' the Doctor asked.

'What gave it away?' Dani asked.

'I heard you call her a sentimentalist when we first got to Malcassairo,' the Doctor answered. 'And you mentioned this when you told me about her.'

They walked in.

'I don't get it,' Jack said. 'We're wearing these, but she put the barrier up the moment he were at the door of the TARDIS.'

Carly popped up from underneath the console. Her chocolate hair was long and straight and her green eyes were exhausted but bright. 'Mental deceptions don't work on me,' she told Jack. 'I'm the Sovereign of the 21st Century. Reality's existence depends on me. You'd be in a bit of trouble if I was tricked by a mental deception.'

The Doctor stared in horror at the contortion wrapped around the console.

'Yeah,' Carly said. 'It's a paradox machine, you've probably guessed. Or what's left of one. I've been pulling it off. I don't think the Master's gonna try to kill mankind until he's got you. The way I understand it, you're quite the leader. Could lead a revolution against him if you wanted.'

'Lock me up, safe and sound, so I can't do that.' He reached past the machine and stroked the console. 'It'll be all right, old girl.'

'Nah.' Carly shook her head. 'That's a bit too thick. You'd escape. You always escape and he knows it.'

'What's he want to do instead, then?' Dani asked.

'Remember Lazarus?' Carly asked. 'Vain old man who didn't want to die.'

'Yeah, what about him?' Dani asked.

'Saxon funded him,' Carly said. 'Then, after you were done, he took the research, perfected it, and reversed it.'

'Oh!' the Doctor exclaimed in realisation, because now they were under the protection of the Impenetrable Barrier. They didn't need to worry about being heard or noticed. 'He doesn't want to lock me up. He wants to age me! A helpless old man! Slow! Weak-limbed! Jelly-muscled!'

'Yeah, pretty much,' Carly said. 'He's also developed a sonic laser with the ability to knock Dani and Jack out for the count and age you. And not very smoothly.'

'He's developed something that could knock Dani down?' the Doctor asked.

'Now that's a laser worth seeing,' Dani murmured appreciatively. Being the species that she was, it was instinct to seek out things that could test her limits. Make her stronger.

'Wait a minute.' The Doctor looked at Carly. 'You said the Toclafane need the paradox machine to kill the humans? But that would imply…you're kidding me.'

Carly, knowing what he suspected, shook her head. 'I'm not. He got the humans from the end of the universe. He was the one who sent out the signal. Told them he could save them. They'd gone mad. They were willing to do anything. And they think killing is fun. Just a lump of flesh in a floating orb now.'

The Doctor, Dani and Jack moved around and started examining what was still attached of the paradox machine and the Doctor found the gage.

'This thing will be ready to use at two past eight in the morning,' he said.

'Which is about when the Master will realise that this thing isn't quite as operational as he thinks it is,' Carly agreed. 'He'll come to see what went wrong and find just because he took down the ship's shields doesn't mean it's unprotected. He'll scan this thing and—whoops—there goes the plan for world domination. Of course, he'll probably still try to get us.'

'Yeah, he will.' The Doctor grinned. Then he looked out the door in confusion. 'Do you mind answering me something.'

'Ask away.' Carly waved her hand.

'The amount of energy that you would be need for this barrier would be phenomenal,' the Doctor said. 'And if it came from your mind, it would take a lot of energy to keep up and keep strong. In theory, you'd have to concentrate very hard to maintain it and, even then, by this time you should be starting to waver. But not you.' He stroked a bit of the console that Carly had uncovered, soothing the ship. 'You keep it up and keep it strong as you're removing a very complicated paradox machine from a just as complicated timeship. You're not wavering and you're not faltering. In fact, it seems more like you're maintaining the barrier as a subconscious act.'

'Mid-conscious, actually,' Carly said.

'Eh?' the Doctor asked.

'As the Sovereign, I have three levels of consciousness as opposed to the normal two that most humans have,' Carly clarified. 'Most of the time, there's the conscious and the subconscious. But, with me, I've got three. I've got the foreconscious, which is where my every controlled action is centred. My mid-conscious is semi-controlled, semi-automatic. And my subconscious is every automatic action. The ability to erect the barrier is in my mid-conscious.'

'So it's staying up on automatic?' Jack asked.

'Yeah,' Carly agreed.

'But that power…' The Doctor shook his head. 'Dani said you were a human.'

'I am.' Carly yanked another piece of the paradox machine off and discarded it. 'When I took the mantle of Sovereign, my brain was altered so I could take it. Then, when 2099 turns over to 2100, I pass it onto the next guy and my brain returns to normal and filters so my head doesn't explode. Dani told you that too.'

'Amazing.' The Doctor grinned. 'To think the human brain could be altered into something that advanced and then revert back to its original state.'

'Don't want one person getting too much power,' Carly said. 'Besides, it didn't hurt at all. Back then, my human, mortal mind wasn't quick enough to feel the pain of the metamorphosis. Because all that power and knowledge and endurance was filtered to me in the millisecond that 1999 became 2000.' She turned away and started working on the next part of the paradox machine. 'Other people, though, aren't so lucky. The Sovereign is the only one with the luxury of painlessness and going back to what they were. Like, in this case, takes about two years.'

'Come again?' Dani asked. 'Who's changing?'

'Doctor, do you remember that hallucination you had on 42?' Carly asked. 'The one I wouldn't tell you whether it was real or not? Well, it was.'

'What?' the Doctor demanded.

'And it wasn't a hallucination,' Carly went on. 'It was a psychic link. Your ship here created it to give you a strong enough incentive to fight off the sun. She sent the link back in time and through the Medusa Cascade to reach her. It works both ways too. A few minutes before you saw her, she saw you.'

'Blood and bone!' Dani suddenly exclaimed. 'You did do it, didn't you?'

'Yup,' Carly chirped.

'Did what?' Jack asked.

'Moved her through the Rift,' Dani said. 'That energy that went through the Rift and disappeared. That's impossible. But Carly could convert a human body to energy, shift it through the Rift and then make it human again.'

'Actually, I just took her to the Rift,' Carly responded. 'The whole converting into energy, shifting through the Rift and turning back into a human she did on her own.'

Carly was completely unsurprised when the Doctor suddenly shot forward, twisted her around, grabbed her collar and slammed her against the piece of paradox machine she was working on. It hurt but Carly didn't fight back. The guy had a very good reason to be angry.

XXX

The Doctor knew what she meant. Carly remained passive. Dani had already figured it out and if Jack hadn't, this would have given it away.

'She had the vortex in her head,' Carly said. 'You had it for a fraction of the time she did and you were forced to regenerate. Yet, with her, all it caused was memory loss. And that memory slowly came back over the following year.'

'Why?' he all but snarled.

'You wouldn't be able to take it if she died,' Carly said. 'Like Dani said, I'm a sentimentalist. I love a happy ending. So I made a deal with…well, for simplicity's sake, let's call them the Powers That Be. If I took full responsibility for the conversion, they'd allow her to last for as long as you do. The first thing to happen, happened slowest. The last year you two were together. Her mind strengthened so she began to remember what happened that day and a Translation Cortex developed in her brain. That was the only painless part of the conversion. Between all three parts of the conversion, there would be a lull where she would adjust to the changes before the next part began. The next part was her mind amplifying to the level where she could harness the power that remained inside her at will. That's what you saw that day. We used the lull between that and the next part to get in here. Not five minutes later, the final part began. Her body has to convert. That's so she doesn't burn and it also stops her ageing. That's what's happened.'

The Doctor felt all his muscles were locked. Dani and Jack came and stood beside him. They gently grabbed his arms, both knowing what was going through his head.

'We'll help Carly get rid of the paradox machine,' Dani told him. 'You go to her.'

'She needs you, Doctor,' Jack said.

The Doctor released Carly. He turned and ran. He ran down the corridors of the TARDIS to the room he hadn't set foot in since he lost her. He activated the panel and slowed to a stop inside.

There she was. Her blonde hair was fanned across the pillow and the duvet was pulled up over her. But her body was covered in sweat and her muscles were tense in pain. As the Doctor drew closer he could hear her quiet whimpers of pain. He sat on the edge of the bed and her eyes snapped open. Her bloodshot hazel eyes looked right at him in relief.

'Doctor…' she whimpered. 'It hurts…'

'Shh.' He laid down next to her and wrapped his arms around her as she crawled onto his chest. 'I know, Rose, love. I know.' He kissed the crown of her head.