Seriously, I thought I was getting too old for this, but the Doctor has reawakened my excitable fangirl heart after all.

So, I was working on that DWHP crossover of mine (I'll get back to writing that soon!) when I realized that I rather like the potential harmony between the Doctor and Jack. Both of them will grow incredibly old, and both of them suffer from losing everyone around them over and over again. If only they bothered getting along properly, their mere friendship might turn the universe into a less vast and lonely place for both of them.

Eventually, I came up with a framework to explore the idea of the two of them supporting each other throughout time and space and half an eternity without being together per se.

But in any case, a list of warnings before we begin:

- Captain Jack means innuendo, thus there's lots of flirting and ambiguity involved.

- There will be some Torchwood references. There will be some spoilers, but nothing beyond what you normally accidentally find out within this fandom.

- The chapters are sorted by contextual continuity. For that reason, the story won't progress chronologically for either Jack or the Doctor.

- Lastly, I'm trying to tell the whole story of the two of them (rather compactly so), which means that ultimately there will be death and dramu…to a certain extent. Also, some regeneration fun and temporary death…and stuff.

So now, onto the story!

Recurrence

Disclaimer: Doctor Who belongs to BBC.

Setting: AU from Last of the Time Lords, with Jack choosing to travel with the Doctor rather than returning to Torchwood right away.

Part 1

Comprehension

Anno 3 797 010 340 B.C. – 10th Doctor, 936 – Jack, 632

The Doctor's point of view.

"Legends say that life came into existence mere hours after space-time itself," the Doctor mused as he strolled through the console room, "Of course, those were mere stories told to young time lords, but it can't hurt to find out after all, now can it?"
He had been slightly anxious about this, but with excitement bubbling up inside of him he just had to grin in anticipation. "So that I may perceive whatever holds," the Doctor quoted in a low hum, "The world together in its inmost folds." He had been itching to visit this particular event, yet reason had always kept him from doing so. But then his latest faithful companion had managed overruling his rational decision after all. Bad influence, that, for better or for worse.

Quite a while had passed since he had picked the captain to travel with him, and regardless of his own instincts screaming at him, regardless of the inherent wrongness of an immortal being, he was grateful to experience wonders like this with someone dear to him. Wonders like vastly condensed matter visible above their very heads without burning or squeezing them out of existence.

"Captain Jack Harkness," he announced brilliantly, "Meet the beginning of the universe!" With that, he pushed a pair of wooden doors open and was thrilled to lay eyes on thriving greenery under a blindingly bright sky.

The immortal grinned at him, and together they stepped out into a forest of giant mushrooms and even bigger palm trees. Everything they looked at, the moss, the pebbles, the mountains in the far distance, was shining in the brightest colours and so ludicrously oversized it almost felt surreal. And yet, they were standing in the middle of it – the first forest after the Big Bang, and it was impossible in any way.

"I can't believe this," Jack breathed, staring from a bright sky of pure energy to the very inhabitable forest they had just entered, "We're standing in a dense plasma of electrons, and still…this. How can that be?"

The Doctor smiled back softly before looking up at the sky as well. From the strange metallic taste in the air to the slight humming the back of his head, a lot felt strange in this place. But Jack had just asked the real question, and the Doctor had been wondering exactly the same thing. "This is the earliest possible time the Tardis can travel to," he explained with a frown, "but we're still some hundred thousands of years off the Big Bang itself. Assuming the universe has been expanding at random for quite a while, it would be highly improbable not to find some sort of order somewhere." His gaze travelled back to the radiant sky, and he waited for his wild guess to be disproven. It's too soon.

And of course, his loyal companion didn't fail him. "This is a planet, Doctor," Jack informed him, "A planet amidst a mass of highly condensed matter." Their eyes met and he added, "A planet with a flora and an atmospheric protection against raw energy."

"Highly unlikely," the Doctor agreed with a nod before strolling off in one random direction, "but only a bit less likely than someone hiding a planet in the beginning of time."

Jack's eyes suddenly lit up. "I like the sound of that," he grinned and jogged up to his friend, "Just think about it. What could be so important someone would hide it here?"

The Doctor nodded wordlessly as he took in every detail of the unlikely world around them. Small pinkish insects, apple-like fruit that hung from lianas, thin pathways that could as well have been created by intelligent beings and always, everywhere, that unnerving iron taste on his tongue.

"Maybe another time lord?" Jack guessed helpfully, "We found the Master at the end of the universe, this wouldn't be so far off."

Brushing a particularly large branch out of his way, the Doctor frowned. "Maybe," he drawled, "but maybe not." Decades may have passed since then, but he doubted he would be ready for another disaster like what he had gone through with the Master any time soon. In any case, he had a feeling he would not have to worry about that anyway. As they were venturing onward, the path widened ever so gradually, almost as if it was welcoming them. Was it only him, or was the humming slowly growing louder?

Suddenly, a hooved turtle shuffled out of the bushes, crossed their path and vanished underneath a giant banana. "I don't even know how to phrase this," Jack commented as he crouched to look after the strange creature, "It's like…someone experimented without really caring."

"And they stored everything on this planet at the beginning of time, hidden away from any laws?" the Doctor finished Jack's thought, "I think it's deeper than that." He thoughtfully picked a cherry from a nearby mushroom tree and inspected it. "It feels like…a by-product." Just at that notion, he saw something glinting through the branches and curiously stepped closer…and he quickly backed away in surprise.

Another bizarre detail about this planet was the utter absence of weather whatsoever. No wind, not even a breeze had warned him of the even ground turning into a steep cliff line mere metres beyond the mushroom's leaves. What caused even more confusion, however, was the sight that greeted them. Within a chain of mountains laid a perfectly round, peaceful plain of gentle colours, amidst which a perfectly shaped, emerald lake was sparkling brilliantly.

Jack whistled in appreciation, but the Doctor only stared. "This is…too much," the time lord whispered, "too orderly."

"That's a freaking fractal lake, Doctor," Jack spoke in wonder, "You can't tell me that this was not created."

"I'm not saying that it wasn't created," the Doctor replied and finally tore his gaze off the landscape in front on him, "but if I were to come up with an entire world, I wouldn't do it like that. I would try to create it in such a way that it could last. But this…" Stepping away from the cliff, he walked back onto the pathway, taking in all the tiny and giant obscurity it held, "Just look around. This whole world. Time, together with physics and evolution, would never create such a thing. Nothing we see here can develop by conventional means, let alone survive for long. You're absolutely right, this world is constructed…but not intentionally."

Jack followed him slowly, an eyebrow arched in confusion, "What do you mean?"

"We're close to the very origin of everything," the Doctor explained and put on his glasses to get a closer look at the crimson cherry he was still holding. "If we could get further back in time, we would, at least theoretically, end up at a single point of convergence, and not even the time lords knew what really happened then. If even the time vortex itself is condensed to one point there, it is entirely possible for knowledge of the future to seep through, resulting in, well, this." He handed Jack the cherry and waited for his friend's eyes to widen. From a distance, the fruit looked startlingly normal, but once you examined it more closely, you could make out tiny inscriptions on the surface, formulas and quotations alike.

'Beautiful moment, do not pass away!' he heard Jack's voice above the constant humming in his head, and the Doctor nodded in agreement. "Goethe, good man, brilliant mind," he mused as he walked around thoughtfully, "always a bit difficult, though. But the real question is: how can we read his words on a cherry at the beginning of time itself?"

Jack finally averted his gaze from the fruit to blink at his friend in confusion. "So this is an anomaly?" he drawled, "All kinds of information flowing together to form a random world just because?"

"Well, it's either that," the Doctor replied as he pocketed his glasses again, "or intelligent design." Their eyes met for a moment, and he continued with a slight grimace, "If, right now, the universe truly was being created by some sort of higher being, a laboratory like this one would be nothing out of the ordinary." Walking around, he tasted the air once more, and if his sense were not failing him, the iron stench was growing worse and worse.

'Seriously, a god?' he heard Jack answering, 'But doesn't that mean that this planet, right here, right now, might not be a laboratory…but a home?'

Whirling around, the Doctor stared at the immortal with wide eyes. "If you're right," he whispered and approached the pathway once more, squinting in the attempt to find out where it led, "then the universe has an origin, and it is right around the corner." He drifted forward without really noticing, and the further he went, the louder the constant background noise grew. No matter whether it was a creator, an energy surge, or anything, it was attracting him, and he was intrigued.

'Doctor, what's happening?' he heard Jack behind him.

He was exploring, of course, what else would he be doing?

Suddenly, he felt a hand on his shoulder. With a blink, he halted in his step and turned around to find his companion frowning back at him in worry. "Doctor," Jack stated slowly, "Where do you think you're going?"

The Doctor noted in surprise how they had moved quite a distance in the meantime. "Aren't you interested?" he grinned in barely concealed excitement, "There might be a higher being here, you said so yourself!"

Jack's eyes widened. "I said no such thing," he pointed out carefully.

The Doctor's face froze. What?

'How do you know where to go anyway?' Jack added silently.

They looked at each other for a long moment before the Doctor's face twitched into an uncertain smile. "Don't you hear it?" he asked, "the humming that's growing louder the further we go?"

Jack took a deep breath and a hesitant step back. "I don't hear anything, Doctor," he whispered quietly and trailed off, 'but can it be that you are reading my thoughts?'

…what?

"Nonsense," the Doctor replied with a frown, "time lords may be psychic to a certain extent, but that is off the scale."

Jack arched an eyebrow. "And yet you just answered a question I never spoke out loud," he commented, "Maybe there's something godlike close, or maybe the vortex is seeping through, but in any case, it's influencing you."

The Doctor opened his mouth and closed it again. So it was true? He had somehow been hearing Jack's mind rather than his voice?

'And I really can't promise to keep my thoughts in check,' the immortal commented sheepishly, and now that he knew what to look for, the Doctor could actually tell the difference. Rather than registering with his ears first, that last sentence had entered his consciousness directly, and he wondered whether to feel violated or intrigued by that strange sensation. "Well, this is definitely new," he pondered with a slight frown, "But I guess as long as it's only slightly enhanced telepathy, I can manage." With that, he finally allowed himself to actually meet Jack's eye again and took a deep breath. "Are you afraid?" he asked and extended his hand, "Or do you want to venture on with me?"

Jack did not even take the time to reconsider. "I'm in this with you, of course I am," he declared as he grabbed his friend's hand with a grin, "You need someone to watch your back, don't forget that."

The Doctor smiled, "Thank you."

As they kept walking, across a clearing made of ice, through a herd of fluff ball sheep and across a tree formed to be a bridge, the Doctor felt…grateful.

'Beautifully grotesque…'

Grateful for the universe, for life, and for everything that made his own existence so pleasantly worthwhile. Adventures like this one, so grand, so meaningful, so frightening and exciting at the same time. "Quite a scary thought, isn't it?" he wondered aloud as he halted to examine a strangely familiar pattern on the thorn of a gigantic rose, "We're at the origin of everything, and apparently, literally everything can happen here."

"…everything, eh?" Jack replied with a grin and an arched eyebrow, and the Doctor didn't need to hear any of his friend's thoughts to understand – and ignore – the innuendo. But more importantly, the immortal was flirting to hide his actual thoughts. The humming inside the Doctor's head had grown louder and louder, and yet he could hear Jack's mind quite clearly, 'The air tastes of blood.'

And he was right.

"We should leave," the time lord whispered in a shaky voice, "we're headed for a singularity in time and space itself, but if the Tardis can't reach it, then neither should we." He took a deep breath, and it smelled horrifying. "And the closer we get, the more strange things will happen." He gulped, and he sought his friend's eyes for any sort of affirmation.

Jack's tense expression turned into a hesitant smile. "Yes," he uttered, "Yes, we should leave."

So they agreed, wonderful. Nothing left to do here, nothing at all. They turned around and would return to the the Tardis, and they would be the only ones knowing of this wondrous, strange, creational world that stood at the very beginning. Whatever was truly happening at the end of the pathway was not that important, was it?

'Nothing is worth losing you.' He blinked at Jack, momentarily confused. Again, the immortal was right, wasn't he? Just as the question about the source of everything itself, the atmosphere was terrifying, and if the origin's presence had widened the Doctor's senses from afar and beyond reason, then its proximity might cause the unimaginable.

So why…didn't he want to return yet?

His companion had been dragging him back towards the Tardis, reasonably so, but the time lord only consciously noted it when they suddenly stopped.

"Doctor," Jack whispered, his eyes wide, "the bridge is gone."

Finally, that did gain the Doctor's attention. "…What?" he replied and approached the hilariously deep canyon they had crossed earlier.

"It was definitely here," Jack stressed and ran hand through his hair, "A single solid tree formed like an actual bridge, with ledge and leaves and everything."

The Doctor arched an eyebrow at his friend before looking back toward that all too alluring pathway. "Whatever is there wants us to come," he concluded slowly.

A hand grabbed his wrist, and he was momentarily confused about how he had manoeuvred himself so far off the canyon again.
"Or maybe it's you wanting to go," Jack suggested quietly and met the time lord's frown with a serious expression. "Whatever created this world is reacting to you," he explained and pulled his friend into a hug, "not to me, but to you." He took a deep breath and continued, "And maybe it's even changing you." He released the time lord at last, and his gaze was piercing. 'If you can read my mind, then your thoughts recreating the world around you might just be the next step.'

Naturally, the Doctor was unsure how to take that piece of information. How would Jack even come up with something as absurd as that?

"Look, if that was true, I could just urge that bridge back into existence," he offered and looked back at the canyon, "I could turn the sky red and I could create a wasteland right here and I could do so much more, but I just can't." He found Jack smiling tiredly, and he was confused again. "No one's meant to have a power like that," he added, "and no one can." Something shifted in the corner of his eye, but his mind was too preoccupied to take further notice. Why was this topic agitating him so much anyway? Even if it was possible, he would never want such a horrible ability…or would he?

"What about the Tardis?" Jack asked innocently, "Could you bring it here, hypothetically?"

The Doctor blinked once more. What was his friend getting at? Hypothetically, he could send her anywhere, but the point was that he would not need to anyway. He would be able to accomplish anything from that very spot. Anything he ever wanted, anything he ever could want, and most importantly…

"Jack," he whispered almost desperately, "I could save everyone we lost."

The immortal's eyes widened dramatically. "Doctor, stop it," he replied hoarsely, "You…you can't." With a deep breath, he tore his incredulous gaze off the Doctor to drag him along in a seemingly random direction.

"That's my point exactly, I can't," the time lord replied indignantly.

Again, Jack sent him that bitter smile. "You know, Doctor," he commented as he produced a key from his pockets, "You began citing Goethe even before we found his words imprinted on a cherry." With that, he unlocked the Tardis that had appeared out of nowhere and quickly pushed the Doctor inside. "We need to get you out of here," he insisted, "Right now."

The time lord's hearts skipped a beat as he finally realized what was happening. His wonderful friend had yanked the doors shut behind them and was dashing towards the console, already starting with the engine a second later.

All the while, the Doctor stood frozen. The sound of the universe was echoing through the room, taking him millions of miles and billions of years away from that place.

But the constant humming never left his head.

He had walked with his eyes open, but he had not seen. His last glimpse of the impossible planet at the beginning of time had not been the blindingly colourful mushroom forest he had entered before… but a deadly desert under a red sky.

And it had been his doing.

Jack had noticed the Doctor's strange new ability, but he himself had not…and that was the worst part. A time lord with the power of creation was a person to be feared, but a time lord willing random thoughts into existence without even realizing it would end up – No. He could not think about it. He would not allow himself to accidentally –

He loved the universe, and he would do anything for it to stay as wonderful as it was.

"But there's no joy in self-delusion;" he whispered as he strolled towards the console, "Your search for truth ends in confusion."

For whatever reason, he had gained a power that endangered everything he held dear. Just as Jack had suggested, it might have been the origin reacting to his thoughts. As such, everything should turn back to normal as soon as they left that strange world, but...

They had crossed time and space and had arrived somewhere around the 42nd century.

And he could still hear the humming in his head.

From the Tardis' front door, they were looking down at the one planet the Doctor had learnt to love so much.

Earth.

He would never grow tired of marvelling at its beauty, and thus he once again etched every detail into his mind…for he doubted he would get another chance to for quite a while.

But – he had to be careful; he had to keep his mind clear.

On cue, Jack met his eye and broke the silence. "Are you…better?" he asked.

The Doctor smiled back tiredly. "I wish I was," he replied, choosing his words carefully, "but the humming's more persistent than that." He had become too powerful for the universe to handle, and he could only come up with one solution to that problem. But how could he make Jack understand? "It will wear off eventually," he both hoped and demanded, "Put me in a stasis and go." He should not mention his most unfair argument, and yet he needed to, "Ianto is alive and waiting for you."

Hurt flickered across Jack's face, but he looked more determined than ever. "You know the deal, Doctor," he chided with a frown and stepped closer, "No matter whether it's radiation or the time vortex itself…" His voice dropped to a mere whisper. "It doesn't react to me that way, and I can take it much better than you."

The Doctor stared at his friend in defiance, yet the moment he opened his mouth to protest, it was captured in a desperate kiss.

Ever so gradually, his mind cleared up.

Eventually, even the humming quietened down.

But Jack's one, most prominent thought kept ghosting through his head.

'Nothing is worth losing you.'

The Doctor smiled bitterly as he caught his friend's limp body in his arms. "We've been travelling together for decades, Jack," he whispered into unhearing ears, "What makes you think I don't feel the same?"

Wide eyes met tired ones.

An hour had passed, and another one, until Jack's body had finally jerked back to life.

The immortal was panting heavily, but his breathing returned to normal ever so gradually.

"We need a new rule for this sort of thing," the Doctor whispered dryly, "I hate watching you die on me." Consciously or not, he did not stop stroking Jack's hair.

And, well, the captain did not seem to mind, either. "It was the most logical decision," he replied with a lopsided grin.

"This wasn't just a bullet wound you took for me," the Doctor explained quietly, "it might, no, it should have killed you for good this time." He had been doing his best not to dwell on that option, but now that he had dared speaking it out loud, he realized that his own lethargy was nothing else…but fear.

Jack's grin froze briefly before he sat up at last. "Don't worry," he laughed and hopped to his feet, flexing his muscles experimentally as he strode through the console room, "look, I'm fine."

The Doctor heaved a sigh before he stood up as well. "Yes, of course," he replied, watching his friend carefully. At the very least, Jack seemed normal enough; he was all but bouncing, and he showed no indications of paranormal abilities.

Normal enough indeed.

But…

"So, where to now?" the Doctor began as he pushed his hands in his pockets and walked over to join his friend at the console, "We could go to Mars, or we could go to Cardiff, or we could try to make sense of whatever just happened." He took a casual look at the main screen, but kept watching the immortal out of the corner of his eye.

Jack had been checking their current location's data and did not seem too fazed by the Doctor's words.

But his mouth was twitching in agitation.

And so, the Doctor leant closer. "We've been travelling for ages, and I never got around to asking," he spoke quietly, "are you happy like this, Jack?" He tried not to look too concerned, but he knew he was failing miserably, for he saw his friend's eyes widening rather dramatically.

A heavy silence settled until Jack dared trusting his voice again. "What is this really about?"

The Doctor heaved a sigh. "About us," he said simply.

Jack could not help frowning. "You're angry I saved you, is that it?" he deduced indignantly. "Friends help each other, you know. I've been playing by your rules, Doctor, but expecting me not to care goes a bit far."

The time lord finally allowed himself to smile again. "That's just it, Jack," he mused as he leant against the console to look at the ceiling, "I didn't know."

He wondered how to phrase his thoughts, and thankfully his friend did not urge him.

"I might only have gotten a glimpse," the Doctor explained carefully, "but I've seen enough of your thoughts."

Jack's eyes widened, and he quickly threw his hands in the air. "Look, I'm really just imaginative," he justified himself and frowned at his friend, "and you know that."

In spite of himself, the Doctor could not help chuckling. Frankly, he had come to terms with Jack's unique nature long ago. The man was flirting with everything remotely attractive and had probably succeeded more often than not. Thankfully, though, he had never actively approached the Doctor that way.

But along with the strangest memories, the time lord had gotten a glimpse of his friend's actual devotion to him without even intending to.

And, honestly spoken, the Doctor was not even surprised. "I met older versions of you, too," he admitted with a shrug and continued, "I should not have seen what's on your mind, but now that I have, I want to make the best of it."

Jack's grin was a hesitant one. "…Dinner for two?"

The Doctor shook his head with a smile and reached for the vortex manipulator strapped to his friend's wrist. "I want you to go," he announced as he added a number of settings with the sonic screwdriver, "and I want you to return."

Jack blinked from the device to his friend and back in confusion. "And I want you to stay," the Doctor added, "whenever and whichever way you please."

Once again, Jack blinked. "So you're…not really dumping me, are you?" he asked hesitantly.

"You're not just another companion, Jack," the Doctor spoke with a wistful smile, "and you really don't need to keep trying to impress me. You've gained my respect so very long ago." He sighed softly before going on, "But you, too, have people and needs to take care of, so I can't just keep you here like a bird in a cage. Not anymore."

Finally, Jack lowered the vortex manipulator and gulped down what appeared to be a huge lump in his throat, "And you won't vanish on me again?"

"You've got my number, so just call me," the Doctor replied with a grin and pulled his friend into a hug. "We've got so many great adventures ahead of us, after all."

He closed his eyes and chose not to finish that last sentence.

…and I want to keep looking forward to those adventures until the end of my days.

Thank you for reading this far, and please leave a review!