Author's Note: So I've had this idea for an alternate universe series floating around in my head for a long time but I don't really have the time to write it. But I rather like the idea so I essentially wrote the outline for it in story form. I may eventually elaborate on the events that happen throughout. I'll find out if anyone likes the idea first. ;)

Summary: It scares her. The sensation floating in the back of her mind. A soft tickling, almost. No... It doesn't scare her- it terrifies her... Because she doesn't know what it is. She doesn't know anything. So she does the only thing she knows how to: she runs.

/-/-

SHE RUNS

It scares her. The sensation floating in the back of her mind. A soft tickling, almost.

It merely haunts her most days, stays out of the way and out of her conscious thoughts. But it's still there and when she least expects it, it rushes forward.

It makes her dizzy, gives her vertigo when she travels more than ten kilometres.

No, "scares" isn't the right word. It doesn't scare her- it terrifies her. It terrifies and reduces her to panic when she tries to identify it, when she tries to think about it, when she wonders what is causing it.

Because she doesn't know what it is. She doesn't know if it's nothing- a mild flu that has persisted for almost five months. She doesn't know if it's an alien disease or mind control or something equally as bad. She doesn't know if it's a result of living in a parallel universe, though of course Mickey and her mum would have their complaints. And yet they didn't spend a fraction of the time that she had on the TARDIS- excessive atron energy? Or vortex energy? His TARDIS wasn't compatible here after all.

But no. She doesn't know anything. She doesn't know what to do to help herself. She doesn't know who to trust to tell about it. She doesn't think there's a single doctor here that's competent enough to examine her. There's only one doctor with the answers she needs and he's sealed off from her, another universe away, a void separating them.

So she does the only thing she knows how to: she runs.

She packs a few pairs of clothes and tightens her favourite pair of trainers and scribbles down a note for her mum to find. She takes the family credit card with nearly unlimited funds and one of Pete's cars and just goes. She has no destination in mind, no expected date of return, she's just running. And, when she runs out of land, she leaves the car behind and picks a spot on the map at random. As she flies, the world goes nearly black and the noise humming in her mind goes mad with volume and she imagines that the flight attendants think she's nutters.

She never flies again after that. Never drives either because the vertigo begins to increase and she can't risk the danger to others. No, now she literally runs from here to there, following roads that intrigue her, paths that look practically forgotten. She walks too and enjoys the scenery, because, after all, half the fun of running is taking the time to slow down and see where you've ended up.

She can run all she likes but it doesn't chase away the sensation. No, in fact it only makes it grow. Because now she's stumbling into towns with aliens and badies and she can't not help. She uses every lesson she learned from the doctor, every piece of information and distraction technique she can remember of his and she fights her way through invasions and near catastrophes. And with every reminder of alien life, with every energy field she encounters, the sensation just grows. It's beginning to absorb her mind. Beginning to grow too loud to hear at night. Beginning to make her dizzy even as she stands completely still. Sometimes she thinks she can feel the rotation of the Earth, but it's more likely that she's just going mad.

She started with a backpack-duffel to house about three weeks worth of laundry. She managed to wash it here and there, keeping most of her clothes intact. But as the number of her adventures and their difficulty increased, her wardrobe gradually declined to the point that the size of her bag was useless. She ditched it in favour of a lighter, small over-the-shoulder bag with a few changes of clothes easily fitting in there.

But, eventually, she had found her simple style. The one pair of dark jeans that had survived two Kritalin invasions, three near-death falls, one Auton attack, and- most importantly- a fall through dimensions, had become her last pair standing and the only pair she would wear. She held onto a few t-shirts for a while, no matter if they had been minorly damaged. Eventually she lost even those when her bag wasn't worth going back for.

The most important part of her wardrobe was a bit of an accidental gain. Two time agents from the 51st century (she didn't dare ask about Jack, not that she imagined that was even his real name) had been investigating the same time disturbance as her. Gringords, big, green reptile aliens with time travelling abilities had been using Humans to power their newest weapon. The three of them managed to stop the Gringords and the one time agent (Krysta) had left her jacket with Rose. She loved it. It was definitely from the 24th century, not the 21st as Krysta had thought. She could tell because the comfy blue material warmed and cooled against the weather, keeping her in perfect condition to be wandering around Europe in the cooling autumn.

She would have preferred to never stop at hotels- she tried her best not to spend Pete's money and, whenever she did, she made sure that she paid in cash. She didn't want him tracking her. She didn't want to be found.

But there were some nights, some nights when the sensation in her mind was unbearable. When she felt as if someone had punched her in the gut, when the urge to vomit or collapse was too overwhelming. These were the only times when she stripped and scrubbed away the filth of fighting and running. When she carefully washed her one remaining outfit that had become something of a uniform to her- had become her pullover and leather jacket, her pinstriped suit. These were the few times she let herself look at her new appearance, let herself marvel at her hollowed cheeks and smaller waist, her leaner muscles and shorter hair, her decidedly normal and yet peculiar attire, her aged eyes. She was becoming something else, someone else. She wasn't the same girl who the Doctor had left here, the one he had said goodbye to. She was growing and expanding, becoming more. Just like he taught her.

And yet she wasn't sure if she was growing in quite the way he would like.

She ran from the sensation in her mind, determined to ignore its existence until it disappeared, until it left her alone in this miserable world. Even though she wished for it, she secretly hoped that it never would. It was the only familiar thing she had left.

Some nights she glanced in its direction, looked deep into herself to find the source of the humming and the murmuring, the dizziness and the spinning, but always she was too afraid to actually gaze on it. Too afraid to truly see it.

Until Buenos Aires.

Only once all of Europe and Asia and portions of Africa had been explored did she decide that a boat couldn't possibly reduce her to the same vertigo that the air plane had over a year ago. She had explored the bottom of South America on up, finding small problems and testing her solutions. But then she was in Argentina, up north in the capitol city. Aliens truly seem to like capital cities. She can't explain it, but it's true.

They were a race of changelings. Her initial suspicion was that they were plotting to take over official positions and work their way to world dominance. It turned out that she was extraordinarily wrong. They were looking for someone. A non-changeling. What this poor creature did to them, she never did find out. But whatever it was had caused her much misery.

It was the closest she's ever been to death. The utter despair her body had fallen into had kept every nerve firing past its limits until they no longer had the energy to care. Her pain had faded into aches and the cold had transformed it into numbness. Her sight had been taken from her after the first night there. A device had been painfully stabbed into the base of her neck, and with the pinch of connection her sight had deteriorated into darkness. It only took a few days for the world to fall silent. Even the stench of her cell was gone.

She had nothing to ground her to reality. There was nothing to help her feel the passage of time; nothing to assure her that she was in fact alive. Only her mind still exists to keep her sane. And she clings desperately to that.

She exists in memories. Remembers why she's there, why the Doctor would applaud her efforts and why he wouldn't allow her to fade away. She counts her breathes and tries to estimate time. She keeps time and sight and sound alive and falls asleep in her room on the TARDIS. She thinks desperately on her half-conscious memories of the building's layout and of everything she knows of these aliens. She tries to invent a means of escape.

But most importantly she listens. Not to the world, which had long ago disappeared to her. No, she listens inside her mind. She listens to the humming that has scared her for over a year. She clings to the sensation tickling her mind. It's a twisted sort of irony that allows it to comfort her.

Now and then she looks back on it. Glances at it. Lets it flutter slightly forward in her mind but never lets it moves too far. Never lets it grow past its tiny noise.

She finds herself drifting, half between the fantasy of the TARDIS and between the void of sensation. As she drifts, she can almost truly believe that she is there, on the Doctor's time ship, laying in her bed and drifting off to sleep after some adventure. The soft lull of the TARDIS is echoing in her ears, its song a lullaby to her that she misses desperately.

It sounds so real. So soothing. She listens harder, seeks to be comforted by it. It grows as she reaches for it. Suddenly the song reaches a startling peak of beauty and power. Her mind feels refreshed and her body healed and the world explodes in light.

As the world quieted, as her mind calmed and the buzzing of energy tapered away, she understood.

The sensation in her mind had been there for a long time. Since the Doctor regenerated. It was already with her when she was still with the Doctor, overshadowed by the much more powerful TARDIS and the comfort of the Doctor's hand in hers. Now with the world so much quieter, she could notice it. Now, with her mind so fragile, she could look upon it.

And now the world seems to make more sense, the flow of time seems slower and faster and more precise than ever before. She knows now that she has in fact been feeling the world turn beneath her.

How she escapes isn't important, only that she did. She continues to travel, but she isn't running any more. She's recovering, letting her sore and tired body slow down and recover. She lets her mind explore this new capacity, develops her understanding of time and space and everything in between. Because she can learn now at phenomenal speeds and when she encounters advanced (and friendly) aliens, she can learn from them about their technology. And when she encounters new aliens ready to destroy the Earth, technological answers aren't lost on her, in fact they're unbelievably simple.

She goes home after two years. She's a different person now. She's older and wiser, smarter and even powerful, not that she knows it yet. And she sees it in her mum's eyes. Her mum, who had missed her little girl, her Rose who had been spared the life of an alien when she was pulled through the void, gets a bruised and broken and rebuilt woman. A woman who wears only one tattered pair of jeans and a self repairing jacket everywhere, despite her access to stores and her closet. A woman who speaks of warp shielding and transient drives and flux energy shields as if they were telly programs or the latest fashion. A Rose who's ten times more like the Doctor than Jackie had ever wanted.

When she had first come to this universe, Pete had offered her a place at Torchwood and Mickey had encouraged her to join. But she had declined because she still had hope for the Doctor to rescue her. When he said goodbye, she ran. Now that's she's returned, she demands a position. And not just a place somewhere in there, no she demands a rank of power, she demands diplomatic rights, and she demands to be left to her own devices when nothing life-or-death is happening. She has developed her own look that somewhat mirrors the Doctor's "oncoming storm". No one, not even Pete, says no to her.

She examines and reverse engineers and builds all sorts of devices, outfitting them for use on Earth and the Torchwood fleet. She averts wars and keeps Torchwood honest, in the universal scheme of things. She navigates her team into and out of danger like the pro she is. And very easily she gains what one might call respect, even reverence. She becomes more than valued and more than needed and more than a person of authority. She becomes... Rose. Just one word and everyone who has ever had the pleasure of seeing her in passing- Rose in the old jeans and blue jacket- understands.

But then the darkness came. Nothing had prepared her for this. Nothing in her vast understanding of the universe and of spatial and temporal and dimensional mechanics could explain the literal disappearance of the stars. Only one person could possibly know the answer. And there was only one way to get to him.

So she builds a dimension cannon with increasing speed as the understanding comes to her. The walls of reality are collapsing; she can feel it. She can feel everything feeling wrong, feeling thinner, feeling broken. She wonders if it bothers him more than her, because just thinking about it leaves her breathless.

In reality she's surprised that it worked. Surprised by the simplicity that allows her to transport to an alternate dimension. Back to her reality. And she knows it's her reality because it feels right. Because the slight measure of discomfort that she always experiences in her reality is gone. Because the humming feels as though it's calling even louder and even more brilliantly. Like it's happy.

And so is she... until she feels the shift. Something in the timeline that says she's wrong. That tells her that this isn't right anymore. She runs as fast as she can.

But he's gone. He died. He died and didn't regenerate, didn't come back. He can't die. But the woman said so... the woman... there something wrong about this woman, something like strings pulling in the wrong directions. Something is on her back...

She's pulled back into Pete's reality, her new reality. Mental controls, her design. Easier than carrying something. She doesn't much care for carrying things. Doesn't have the pockets for it.

Pete wants to wait a few days, let the energy reserve build back up. Mickey wants her to rest, he knows her too well, knows that the look of horror and pain runs deeper than she's letting on. But she can't stop. She needs to know that that reality was a mistake. That he's alive somewhere, that they can get his help. That he can stop the darkness.

So she latches onto that reality and thinks of one just next to it. Because they are so closely related. She finds herself on a street, watching tiny little aliens float up to the space ship hovering over London. She thinks this one must have a fun story to it, one the Doctor can surely tell her about later. But that's not the important thing right now. The important thing is that the woman is back, she's behind her and saying something. But Rose doesn't know what, she doesn't care what, because it's this woman. This woman is who she's following.

And she does, she focuses her energies and that of the dimension cannon and she follows this woman forward in time. She's the Doctor's companion now. And a wonderful one at that. Donna Noble.

When she finally lets herself return to Torchwood, to Pete and Mickey and Jake, she's so mentally exhausted that she falls onto the floor at their feet and they haul her away. They don't let her get up the next day, or the day after that. They are hardly willing to let her leave after three days of rest but they must. Six thousand more stars that they can count have gone out. Erased from existence.

She knows now what happened. What she saw in that first jump. She knows who Donna Noble is and what that Donna Noble must do. And she knows how to see to it.

When she jumps back in, shakily meeting Donna Noble again, half out of breath and awkwardly trying to explain away the light Donna had seen, she lets her mind free. She lets it seek out the timeline, carefully follows the events in Donna's future. Donna will die, but not yet. Not in the havoc simple aliens will cause.

But she's got a long time to wait for Donna. A long time until she will begin to understand, begin to accept what she must do, so Rose must get ready for her. When she strolls easily into UNIT and declares herself a person of authority, twenty rifles point in her direction and she hardly blinks. She decides that names are best left untouched. Name and rank aren't necessary for respect; she learned that from the Doctor.

It's the most beautiful moment when they finally trust her enough to unveil the TARDIS. It's been closed to them, impossible to penetrate and impossible to utilize. The poor old girl has just been sitting in storage, aging. Dying.

She's dying with every pulse she emits, with every moment she remains separate from the Doctor, with every moment that two of her exist in the shaky-timey-wimey nature of the universe. She knows what she needs to do- she needs to send Donna back. She can feel that piece of time disturbance. One Donna must die for the other to do what she needs to do. And for Donna to go back, a time machine of sorts needs to be jiggery-pockeried into existence. Which is a simple matter, truly, when you have one Rose and one TARDIS.

And when Donna does finally come with her, when she rides into UNIT with Rose absolutely terrified and uncertain of herself, Rose can barely believe her reaction to Donna. She makes herself cold to this version, makes herself see the healing of the timelines, makes herself remember that one life is necessary for the universe- for all of the universes- to survive. She forces the emotions and the bile down so that, when Donna looks at her with an almost excited understanding dawning on her face, her realization that she won't in fact die, Rose can muster an exact replication of the Doctor's, "I'm sorry."

The fact is, the walls of reality have grown so thin that she can see every timeline at once, she can sort through them all and she knows, she knows what will happen to the Donna who turns left. That Donna will live, that Donna will experience the wonders of time and space and the Doctor, and that Donna will save everyone, but that Donna too will die. She doesn't know how or when, but she feels it. She feels brevity of life ahead of the woman.

How can the Doctor live like this? She doesn't think she'll ever develop the stomach for it.

The future of that reality fizzes out of existence and Rose pushes herself over in time, finding her way back home. Back to her reality. Back to the absence of discomfort, to the presence of comfort and joyous singing.

She armed herself first, naturally. Anything could be there, on that Earth, on ground zero for the disappearance of the stars. And, indeed, there's something there. But it's so right that it doesn't matter. Because he'll be there, he'll find her and together they'll stop the darkness. They'll be together, just like old times, and it'll be fantastic.

And then, once everything's sorted, once the Earth is put back where it belongs and everyone is dropped off at home, she'll explain to him what happened to her. She tell him how looking into the Time Vortex changed her, became a part of her. How she's becoming something more and something powerful and something undefined and despite all that, they'll be wonderful together because they'll be the Doctor and Rose, and now the DoctorDonna as well.

She doesn't get a chance to explain when she walks out onto the beach. She doesn't get the chance to tell him that she can't be stuck there, that she can't stand the discomfort she feels in her mind, the lack of compatibility she has to this universe. She can't tell him that she doesn't need a human Doctor because she already expects that she'll long outlive him. She thinks it might be possible that she'll outlive the Doctor himself. She doesn't get the chance because she understands, she knows why he's leaving her there. All the reasons why.

He wants her to be happy.

He wants to give her everything he's always wanted to give her but never could.

He's too broken to fix a more broken version of himself.

She needs her family now more than ever. She has a nephew to watch grow up.

She has children in her future... she glimpsed them a few times in her desperation.

And because he can't take her with him, because there's something dark and horrible in his future, he knows that already.

Because all of time is telling her that she can't go with him and somehow she manages to listen. She suspects it's telling him the same.

Despite every ounce of understanding, despite every rational thought her too brilliant mind comes up with, she hates him. As she hears the TARDIS materialize, as she hears him leaving her forever trapped away in this useless reality, she hates him so much.

And she hates his duplicate just as much, simply for existing.

He tries to talk to her on their slow drive back home, back to London, but she can't bring herself to look at him. Not yet. Because her brain in so jumbled with feelings and thoughts and temporal alignment and she can't deal with it right now.

Which is why, when her mum pulls into a hotel's carpark and heads inside to get them a room, she considers running. It worked for her the first time. It led her to some of the most brilliant discoveries; it got her away. She needed that right now.

He had been watching her for hours, steadily gazing at her, steadily growing sadder and withdrawn. She was killing his tender, new heart. She desperately wants to go to him, to hold his hand and stroke his cheek, to promise him that everything will be all right. Because she knows that it will be- she wishes that she couldn't see how her life would play out with him. She wishes that time wasn't telling her to get over herself. She wishes she could sit down and have a good cry. But that's not in her anymore.

Everyone filters into their rooms for the night. The Doctor- no, not the Doctor, someone else, something else, but still... still the Doctor- was given his own room, her mum and her in another. Jackie made her shower first and made her promise to get some rest while she took her turn. But Rose couldn't sleep. Rose had never planned on sleeping. Just like she did before, a note was left on the night stand and her trainers were retied tightly and armoured with her 24th century jacket she walked out, walked away and found her wind as she ran through the night.

It takes her three days to stop running, and that's mostly from the fact that she dropped dead from exhaustion in some tiny city somewhere.

It takes her another five before she confronts all the thoughts burning through her mind.

She wants her Doctor. She wants the life with him she had been promised, she wants the life with him that she loved and that created this person she is now.

And she wants the life she knows is ahead of her. She wants to have the gentle human Doctor, the one who will be able to express his feelings, who will be able to love her and marry her and bed her and eventually raise children with her. She wants the life the Doctor thinks he gave to her.

This man isn't her Doctor. He's human and he's part Donna and he's completely trapped on Earth, in this time.

But he is her Doctor. He's been shaped by the same memories and experiences; he's just as dark and as angry and as vengeful as her first Doctor had been, and as her second had been without her, she suspects.

He's the Doctor, same face, same memories, different personality, different body- a regeneration for sure. She learned to love the other Doctor, she learned to realize that the Doctor, no matter his appearance, is still the Doctor.

But now he'll die first. Now she'll watch him age, watch him whither with exhaustion and illness and age and eventually succumb. And her? She'll still be this young woman, still living on, saviour of Earth. Without the Doctor. She can't survive that.

She can't fall in love and loose him. She can't live on forever as everyone dies around her. She can't walk the universe forever alone.

It's the first time she understands the Doctor to his fullest. Why he travels alone and why he travels with others. Why every adventure thrills him and pains him beyond imagination. Why he'd never dare fall in love with a human, with a race whose lifespan is a speck of dirt in comparison to his own. Why loving her was the worst mistake of his life.

But this Doctor, this human Doctor, doesn't deserve to be left on his own. He doesn't deserve to be ignored by her. He's been through lifetimes of pain and she thinks that whatever bit of human is left in her needs him, needs however many years he can offer her.

When she finally makes it home again, it's been almost three weeks since they were left at Bad Wold Bay. She desperately hopes that her mum managed to keep the Doctor at bay, managed not to kill him as he explored his humanity. She hopes that Jake and Pete and Torchwood have perhaps kept his hands and brain occupied. She hopes too that he doesn't hate her, that he understands, at least a little.

She sneaks into the house at night, relatively certain that he'll still be awake. When she sees him reclining in his bed, glasses perched on his nose, and mind entrenched in a book, she thinks she can do it. She thinks she can have a life with him for a time. She thinks too that she might hate it. She also thinks that her heart may never recover from this.

When he finally notices her, she doesn't give him time to speak, time to ask questions. No, she kisses him, harder and more passionately than she had on the beach. She kisses away his questions and his misgivings and her uncertainty.

Later they lie together in his bed and she tells him everything. She tells him of the sensation that had scared her, of how she ran and how running had changed her, of the time in Argentina when she fully realized herself and how she had grown from that, of the dimension cannon and finding Donna and what she had to do. She tells him that she did tests on herself and her estimations on just how long her longevity will keep her alive. She tells him that she saw kids in the future and imagines that they must be his and hers. She tells him everything and for a long time he's speechless. When he starts to talk, he tells her everything about himself she never dared to ask. He tells her about the Time War and his childhood and his real name and his hopes for this last life of his.

When he dies only fifteen years later, she wishes that her mutinous body had the same capacity for death. She hates her longevity and hates how little pain and injury affect her body. She almost hates that she has two children to keep her mind grounded in reality. But she certainly can't hate that, she just can't hate having children because they truly are the only things that keep her sane and keep her from launching into the murderous rage she knows she is capable of. They're the only reason, she thinks, that the world survived her grief.

Together, her husband Jon and she had had a son, Alisdair, and a daughter, Donna, who were nearly five years apart. They're practically perfect children, brilliant and perceptive and skilled and who both have only one heart and only one life but perhaps her longevity. Alisdair is the tinkerer and the scholar, who had earned three PhD's by fifteen and who is currently weighing the pros and cons of getting an MD versus a fourth PhD. Donna is the wanderer, the clever one with all the street smarts. She's eleven and remains degreeless- next year she keeps saying to her brother.

It was an average Saturday, a beautiful April morning, and the sun was already peaking through the window. As Rose wakes, she knows that it's today. Today her world will change. She's been waiting for it, keeping the tremor in her timeline always in the back of her mind. She's ready for it. Ready to let whatever happen that's going to happen, despite the fact that she has no idea what it is. No idea what has been waiting for her since that day on the beach. But it's here now.

And so is he.

/-/-

So that's it. That's what's been driving me crazy for a few weeks. If I ever add onto this series (which I hope I get the chance to) I would probably write short stories for: when she runs away, her time in Buenos Aires, her return home (probably from Jackie's POV), a more thorough elaboration on what happens in "Turn Left", her conversation with the duplicate Doctor, and the duplicate Doctor's death/stuff with their kids. Also, if I can ever figure out what happens next, I might write that too.