A/N Thanks once again to T'Kirr for lending an ear on one of the elements herein. She helps keep me sane while writing stories that are slightly the opposite. ;)

Chapter 3

It had been a long and frustrating day of non-success with the Cannon, along with no new answers regarding the brewing issue of unexplained energy readings in Norfolk, leaving Rose mentally and physically drained by the time she returned to her flat that night.

Just a few minutes' walk from Torchwood, the East Tower apartments stood tall, with flats of floor-to-ceiling glass overlooking Canary Wharf's financial center. The lift doors slid open with a 'ding' upon reaching the thirteenth floor. Rose exited and approached the door to her flat. Key in hand, she turned the lock and stepped inside, sliding her bag from her shoulder and dropping her keys with a tinkling clatter onto the glass-topped entry table.

The one bedroom layout featured a generously-sized master suite, open kitchen with bar overlooking the living space, and rich wood floors throughout. It was certainly a posh step up from the Powell Estate, but Rose's interest in choosing it was based on location. Rose had moved in a little over two years prior, shortly after her baby brother Tony was born. With the Dimension Cannon project in full swing and the hours she had begun keeping at Torchwood, it was much more practical to be close by.

Despite this being her current living space, Rose had shown no interest in decorating or turning this place into a home, though it was still decently furnished in a modern style with warm tones and clean lines. Jackie had taken it upon herself to see to that. Even still, Rose had few personal items embellishing the space. But then, she'd come here with no former possessions. All irreplaceable mementos had been left behind either at the Powell Estate or on the TARDIS. Here, other than some photos over the fireplace of her family and the handful of friends she'd made while here, there was little else showing her life in this world – a world in which she had once never even existed.

The flat itself had become more of an extended workspace for Rose than a home. Scattered about were schematics of the Dimension Cannon, graphs of dimensional theories and formulas, and books on advanced subjects she once would have considered foreign, but had quickly become a part of her everyday life and vocabulary. She often wondered if the Doctor would be proud.

With that question came thoughts of past Torchwood missions, the necessary weapons she'd sometimes carried, the unavoidable actions she'd sometimes taken. Now and then a dark voice whispered in reproach, telling her she already had the answer to that question. Still, she couldn't help wonder just the same. How would he view the life she now lived, the woman she had fully grown into and become?

She wondered a thousand different things when it came to him. There wasn't a day that passed when she didn't try to imagine where the Doctor was and what he might be doing. Was he searching for her as desperately as she was searching for him, or had he run and not looked back? Was he okay? Had he been able to pick up the pieces and carry on? Had he allowed anyone else into his life? Would he ever love again?

Rubbing her temples as the recurrent thoughts swirled, Rose walked to the kitchen to prepare a hot cuppa, having no real appetite for a full dinner. She filled the kettle and put it on the stove, then took out her favorite blue mug from the overhead cabinet.

A few minutes later, Rose brought her steaming beverage of spiced Darjeeling to her lips and took a long, appreciative sip. She unzipped her standard black boots and kicked them off as she crossed back into the living space. She sat down on the beige suede couch facing the windows, one leg tucked beneath her as she gazed out at the glowing city skyline through the tall windows, another day's stress fading into memory.

She glanced down at the glass coffee table where the previous day's Sunday paper sat amongst the strewn books on physics and dimensional theories. Her friend and team member, Jake Simmonds, had made a brief mention of it to her earlier that day, due to the Society Column once again featuring her in what they apparently considered to be a newsworthy event. With a smirk, he had suggested she and Mickey give it a read because it might at least bring a laugh. Rose picked up the paper with a sigh, prepared for the latest gossip on the Vitex heiress.

The latest society event she'd attended over the past weekend was hosted by Vitex. The posh evening gala doubled as a fundraiser for a local charity that supported single mothers through transportation assistance and daycare provisions, a cause Jackie had taken up partnership with.

That was all well and good, but Rose just couldn't grasp why the press tended to consider her a person of interest simply due to her relation to the wealthy Pete Tyler. In reality, though, it was the mystery surrounding her that grabbed their attention. Pete had created an identity for her in this world so that those who went back to check her story would indeed find a birth record. It was still tricky, however, explaining her sudden appearance. It had been somewhat easier for Jackie. It was said that the original reports of her death during the Cybermen attack had been false, and she had simply kept a low profile away from the media while recovering from the ordeal. Rose's story was more of a stretch, saying that Pete and Jackie had been highly protective of her through childhood and kept her sheltered from the public eye, to the point that few even knew she'd existed. It wasn't until adulthood that she chose to embrace a more public persona.

It was an unlikely story. Everyone knew that. But no one could disprove it, either. And so, any chance afforded to learn more about her was seized upon by the press. Such as this most recent Vitex function. Her work at Torchwood was kept mostly under wraps, but there was no escaping the occasional spotlight at public events.

Further adding to the mystery of Rose Tyler was that of her 'husband.' Rose glanced down at her left hand where a modest diamond solitaire and gold band glinted in the dim light.

From the start, Rose had made it clear to any man who showed personal interest that she was taken. She had absolutely no desire to form a relationship with anyone else, regardless of how impossible a return to the Doctor might be. She'd eventually found it easier to avoid unwanted advances by sporting a wedding ring. Though she had not worn one while together with the Doctor, they had been married, unexpected and unconventional as it might have been. To the public, the story was told that she had married this past year in a private ceremony to a doctor by the name of Smith who spent most of his time traveling abroad on altruistic medical missions. He was, however, averse to the public eye and chose to avoid accompanying her to publicized events.

The latest Society article focused on the fact that this past weekend's affair was yet another in which her illusive husband had failed to make an appearance. Mickey had accompanied her instead, as he often did. She didn't particularly fancy going to every event alone, and her friend had stepped into the role several times in the past.

Apparently the media was now suggesting that something was brewing between Rose and her unattached friend, Mr. Smith. Who incidentally had the same last name as her 'husband.'

Perhaps the Vitex heiress has a distinct fondness for Smiths, the latest gossip now speculated.

Rose shook her head and tossed the article aside. Didn't they have anything better to do? She wasn't particularly fond of being in the public eye, but even less fond of dragging her friends into it.

Rose pulled out her mobile to ring Mickey and let him know she wasn't laughing.

"'Ello," came the familiar voice on the other end.

"Hey, Mickey," she greeted with a heavy sigh.

"Oh, I know that tone. Don't tell me you've found a band of renegade Mmmphigits bent on world domination whilst walkin' home again," he quipped.

"Very funny. That was one time. 'S not like I go lookin' for trouble."

He snorted. "I'm not even goin' there. 'S just too easy."

She smirked, but put on an affronted tone. "Just for that, I may take back the apology I was about to give you."

He sighed, banter evaporating. "You're talkin' about that stupid story, right? You don't have to apologize, babe. It's the scum press. 'S not your doing."

"Why does my personal life even have to be anyone else's concern?" she griped. But they both knew her real hurt over such articles was in the talk of her absent husband. His absence was the last thing Rose needed to be reminded of. "Anyway," she continued, "I know you hate those Vitex events as much as I do. So don't feel like it's somethin' you have to keep–"

"Pffft. And let you grab all the headlines alone?" he cut in. "Hog the spotlight? Nothin' doin'."

Rose smiled, her voice soft. "What would I do without you?"

There was a pause on the other end. "You may find out one day soon once the Cannon is workin' properly."

Rose hummed non-committedly. "Maybe…"

"Hey, no one's givin' up just yet," he encouraged.

"'Course not," she agreed, tone a little surer, then added quietly," but thanks for the reminder."

"Anytime. I'll see you in the morning then, yeah?"

"Yeah. See ya, Micks."

Rose rang off and pocketed her mobile. She may regret the fact that she was trapped in this universe, but there were several things she was still thankful for – her friends being at the top of the list. She, Mickey and Jake had a strong bond as a team. And while not many could make the transition from exes to best friends, she and Mickey had now managed it with ease. They had both matured substantially from their earlier years. In some ways they were now closer than before.

Rose paused to consider what she would do without Mickey if she were to return to the other universe someday. She had a feeling she might not have to ponder that too deeply. She suspected Mickey would also seize the chance to return to their home universe given the tangible option. He wasn't attached to anyone here relationship wise. He'd dated a bit, but never formed a relationship that amounted to anything serious. He'd been content here early on. It had been a new adventure and one he had made the most of. But his Gran had passed away the year before, and he continued to find himself living in the shadow of Ricky, despite being able to drop the ruse he'd carried for her sake. Lately, Rose sensed that he was ready to take the man he had now become and return to his original universe to thrive. And thrive he would. She had no doubt.

The only doubt Rose had was whether or not either of them would ever get the chance.

-:-:-:-

Depending on one's opinion, it could have been said to be morning onboard the TARDIS. The Doctor had remained in the console room for the duration while Donna finished sleeping. She was right. He'd hardly left this room in days. But the current issue was too important to ignore. Something had been causing a disturbance upon the opposite side of the divisional walls between universes, but despite his efforts, he was still no closer to uncovering exactly what this was or how to stop it.

When Donna found him the next day, the Doctor was still immersed in his work, cross-checking scans and comparing analyses he'd run through the TARDIS' data core.

"I would ask if you ever slept, but it seems like we've been down that winding road before."

He threw a glance over his shoulder to see his ginger-haired companion coming into the room, this time dressed and ready for the day, wearing denims, tunic-length plum blouse and hair pulled up in a bouncy ponytail. She was also (thankfully for the Doctor) sporting a brighter mood.

"Sleep well?" he redirected back to her. "I tried to see to it that things were a little more…peaceful."

"Yeah, I did actually. Thanks." Donna moved next to the jump seat and leaned a hip against the side. "Once I was finally able to sleep without being scrambled like an egg."

"I didn't take the TARDIS near the field of disturbance this time," he explained, turning around and leaning back against the console. "I scanned as best I could from a distance. Made for a smoother ride."

"So when you say 'field of disturbance,' you mean like some sort of…storm in space, or something?" she questioned, attempting to better understand the issue.

"More like the beginnings of a tear," he clarified. "Which could potentially lead to a great big gaping hole."

"What's causing it?"

He shook his head. "Don't know yet. I'm still trying to find out."

"What do you think's causing it? Brain like the one you're always bragging about…you're bound to have ideas."

The Doctor dropped down onto the jump seat, ankles crossed and arms folded. He blew out a breath and made a confession. "I really have no idea. The possibilities are infinite. But whatever is causing it, it's being done from the other side."

"So…something's doing it deliberately, then?"

His brows were knit, voice pensive. "Seems to be."

Donna puzzled it over for a moment as she moved to sit beside him, nudging him over to make room. "You said other side. Does that mean like…another world on the flip side?"

He swallowed, but the word still came out tight and strained. "Yeah."

"A parallel world?" she further ventured.

He paused before answering, eyes drifting off distantly. "Yes."

Donna jumped to her feet, whirling around in front of him. "Doctor, if something's making a way through, then maybe you could get through, too!" she concluded with a lilt of excitement.

"Why would I want to do that?" he asked slowly, his guard clearly up.

She boggled at him as if he'd grown a second head. "Are you serious? You once told me that the walls between worlds were sealed. That there was no way through. And maybe I'm bonkers, but I seem to remember you coming off as just a bit upset about that once upon a time."

"Donna," he cautioned, "I know what you're thinking, but don't."

"Why on Earth not?" she cried, arms flinging open.

He leaned forward, eyes up and locked with hers. "Because we have no idea what we're even talking about here. There's no such thing as A parallel world. There's an infinite number of dimensions. Every single decision we make creates an alternate reality."

"But what if this is the one?" she asked with aching, human simplicity. "The one where Ros–"

"And what if it's not?" he abruptly disputed, throat tight. "There's no telling what this could open up if allowed. It could be a world of nightmares, for all I know."

"Or dreams…," she countered. He made a sound of derision. Her eyes studied him for a moment. "Alright then. So you're willing to just throw away this chance without even trying?"

The Doctor stood to his feet, eyes flashing. "Not trying? Donna Noble, do you have any idea how much I have tried? I tried nonstop for months after the walls closed, and all I could manage was to get a message sent through one tiny little gap before it was sealed forever. But I didn't stop there. I kept looking, kept trying, kept thinking of endless possible scenarios every day and night in the back of my mind, ideas running constantly – futilely. And finally it drove me so far as to…" The Doctor stopped himself and took several heaving breaths as memories he wasn't proud of pushed to the surface. "You have no idea how much I've tried," he finished quietly, body turning away. "Far more than I ever should have."

She was quiet for a moment, then spoke one small question. "Then why stop now?"

He exhaled wearily, turning back. "I told you. I don't even know for sure where this is coming from. I don't know the danger of what might come through if this gap were to open fully. Not to mention the fact that two universes could collapse if it did open."

"Why would universes collapse?" she questioned, trying to get a better understanding of this. "It's just one little spot."

The Doctor stopped to contemplate the query, attempting to put it into understandable terms. "It's like…when you smash through a piece of glass and you're not just left with a single clean hole. Instead, the whole thing fractures and crumbles."

Donna thought about it for a minute. "What if someone didn't smash it? What if they just…I dunno…gave a careful push?"

He shook his head. "It would still crumble. All that pressure being exerted on one side would cause it to cave in."

"But all the pressure wouldn't have to come from one side," she reasoned. "Whatever started this is pushing from there, and you could come up with a way to push from here at the same time."

"Then the force would be distributed and the pressure would equalize…," he murmured, a possibility coming to life in his mind which he had not even allowed himself to consider.

His gut instinct had been to stop it, not assist it. A forceful one-way penetration through the walls of reality posed a great danger. But equalizing the force might substantially lessen the risk. The Doctor's knees nearly weakened at the prospect. And all it had taken was that little spark of simplistic human reasoning to see this possibility which he had overlooked in his single-minded approach. Maybe he shouldn't have even been surprised by that. This had been his experience with humans for centuries.

Donna took two steps toward him, drawing him out of his racing thoughts. "Doctor, it could actually work, couldn't it?" she questioned with quiet, barely contained excitement.

"Yeah," he whispered hoarsely.

"Well, that's it!" she exclaimed with a shout of glee. "Oh, this is brilliant!"

The Doctor sobered, his mind coming back to reality. "Hardly. This is all theory. A theory is a far cry from a sure thing. And even if it could be opened safely, I still don't know where this gap could lead."

"Seems to me there's only one way to find out," she answered determinedly, head cocking in a challenge.

He eyed her sternly. "That, Donna, is a reckless statement."

She snorted a laugh. "You ought'a love it, then. Since when have you ever been Mister I'm-So-Cautious?"

He crossed his arms. "Donna, we're talking about the fate of the universe."

She crossed hers back. "Usually are when it comes to you."

"And I'm usually trying to preserve it. Not jeopardize it. Not again…," he added on a murmur.

She unfolded her arms. "Doctor, I'm not talking about barging through blindly. Do what you've been doing best this past week. Use all this…stuff you've got lying around here to study it. Analyze it. Learn all you can and find a way to make it work and make it safe."

The Doctor released a long breath. He turned and sat back down heavily, looking supremely conflicted.

"Do you even want this?" she finally asked, hands coming to rest on her hips. "I know this is a long shot and there could be risks. I get that. But this is a chance, at least a chance to get through to a place that's otherwise off limits. A chance to…" His eyes shot up. She held his gaze. "A chance to find Rose again. I thought you would want that. I thought she was special to you."

His eyes instantly darkened, drilling into hers. "You think that I don't want to find her?"

She held her arms out. "Well, what do you want, Doctor? 'Cause right now I'm not even sure."

The Doctor's answering voice was quiet, distant and weary as he gazed off, focusing on nothing other than his thoughts. "Oh, I want so many things. Too many things. Things I should forget. Things that can never be. I want my people still in existence. I want my planet still occupying the mighty constellation of Kasterborous. I want my TARDIS not to be as alone and void of her own kind as I am. I want wars to end and worlds to stop destroying each other. And I want–" His hands clenched into tight fists against his thighs, voice straining, words constricted. "And I want my wife – here, smiling, living, breathing, by my side."

His words ended with a catch in his throat.

Donna couldn't even speak.

She stared at him with wide eyes, for once stunned into silence for several long moments. She finally managed to find her voice, words coming out in sheer disbelief. "Your…your what?"

He merely looked up at her slowly, anguish churning behind the storm.

"Y-you mean that Rose was…was your…?"

"Yeah," he whispered throatily, eyes shifting down.

"But you…you never said."

"Does it matter?" he responded, toneless.

Her jaw went slack. A few seconds later it snapped shut. She narrowed her eyes at him, voice rising incredulously. "Oh, mate! You better hope you don't find her if that's your attitude. 'Cause you deserve to be slapped into the next century for that!"

The Doctor abruptly stood, thrusting his hands into his pockets as he paced a few steps. "I didn't mean it like that. What I meant is it doesn't change how badly I want her back, whether she was or she wasn't."

"Then for heaven's sake, take this chance," Donna once again urged, voice soft but imploring.

He was silent.

"You're afraid," she at last concluded. "You just told me about your past attempts, how you tried and failed, and now you're afraid of failing again. Afraid of trying and losing."

She gave him a minute to respond. He finally nodded, the movement barely perceptible.

"But what if this time it works?" she continued, voice desperately urging him to grab ahold of a tiny piece of hope.

"And what if it doesn't?" he rebutted quietly.

"Then at least you would have tried," she finished, echoing a now multi-universal statement.

His eyes finally lifted again, and this time she saw a small spark of life, dim but existent. She inwardly willed with every fiber of her being for this mad possibility to work. Because if his last effort failed and that fragile spark died now, she doubted it could ever rekindle.