It's one of those odd days where the sun is shining and the sky is a kind of beautiful greyish-blue, there are hardly any clouds in sight, and you swear you can hear birds chirping over the sounds of busy London traffic. It's not common weather for an English day so you have to treasure it while you can, like it may never come around again. And who knows? Maybe it won't. Maybe after this day, perpetual clouds and gloom will cover the wonderfully busy city and, even without light pollution, you'll never see the stars again. In that case, the sun would be a foggy globe of hardly-lustrous light trying to break down the grey cover and shine down on the Earth. It would shout, it would cry for help, but of course it couldn't break through, because if there's one thing the sun does, it's heat. It heats the water, which then evaporates and creates the clouds. So, essentially, the sun would be separating itself from you. And, for a while, it wouldn't seem too bad; that is English weather, after all. You don't normally see sunny days. But then, after a couple of weeks, there would be reports elsewhere about cloud cover but no rain. And when the clock would strike seven months, people would finally start to realise that maybe the clouds wouldn't ever go away, and those who hadn't cherished their last sunny moment would have then started to feel an aching in their chest. Like all the happiness was sucked from their organs and their marrow and their very being.

Now, suppose instead of spending your last sunny day outside, you were at work. Or at school, perhaps. Sleeping off a hangover. Sitting in front of a computer, as I am now, and documenting a story as another took place outside your door.

And, just maybe, you were trying to stop a small group of Anicorpus Shifters from multiplying, covering the sky, and taking over the human race, all in the dark and undiscovered third basement of a warehouse building.

Oi, don't look at me like that! It's possible!

Well... It's really only possible if you're a Time Lord.

And that, my friend, is what John Watson was. In fact, he was the very last one.

He went by The Doctor. It was a simple title, but titles were a gift on Gallifrey. His was chosen during the Last Great Time War, wherein his job was to help injured soldiers; to heal his brethren in battle who weren't hurt enough to regenerate. He liked his title, and once given one, that was what you went by. Simple as pudding.

Though when you think about it, and you try and decide on which pudding you're talking about, maybe it's not all that simple. For example, cake is pretty simple - a few key ingredients, half an hour in the oven, and bam! Delicious, flavourful, moist treat. But things like crème brûlée or chocolate mousse are a bit harder to put together, more difficult to cook and serve correctly.

For the longest time, The Doctor considered himself - not directly, of course - cake. Simple John Watson, army doctor. And a good one, too. One of the very best - and, oh, was he ever praised for it! He was given the title of The Doctor, after all. Err - well. He didn't consider himself much of one anymore. Multiple bad things - terrible things - went quite wrong after his title was placed upon him. The Daleks got stronger and mightier, and there were many, many more of them. A dangerous amount, if they weren't already. And fighting them got much more challenging and extremely overwhelming to the outnumbered Gallifreyan soldiers. More men and women were taken down, and there were an unforgivable amount that The Doctor couldn't save, or that were killed before they could regenerate. And The Doctor hated himself for it.

At some point during the war, The Doctor had been shot by a Dalek. And it was... horrible. It felt like pure, raw electricity filling every cell and molecule in his body, like his veins were on fire, like his whole person was being held in a vat of molten rock. It was terrifying, traumatising, and damn near fatal, as every one of those shots were. And then there came the simultaneously body-ripping but somehow uplifting feeling of the Time Lords' regeneration process - all of his structure bursting and reforming into a new body; healed, but weak. The Doctor thought he might die then, writhing in the dirt of his home planet with a plethora of enemies surrounding him and his platoon. He could be shot again in any of those moments. And what good was he then, if he couldn't help his soldiers because he was completing the regeneration process, or worse, dead? The Doctor was moot if he couldn't do what he was designed for.

When his regeneration was complete, he felt energised. New and clean and jumpy. But it wouldn't last, and he knew it. He needed time for the entire process to finish, but... His soldiers – the people he had the occupation of healing – he couldn't leave them. And so he did possibly the most stupid, dangerous thing a newly regenerated Time Lord could do.

He got back up, and he started working again.

The Doctor could feel his body protesting. It showed, physically, in the form of occasional wafts of sparkling gold, gaseous material that emanated from his fingertips and forced its way out of his lungs. It hurt, more than anyone could imagine, but he continued on. He wouldn't rest. Some of his soldiers would try to make him, normally when a whimper escaped him at the same time as the golden life force.

His new body was deteriorating because of it. Dead centre in his left shoulder, where the Dalek's ray had hit him in his last body, evidence of the shot had started reappearing. It was a starburst scar, rather large, and – due to the electricity of the weapon – it had lit up all the veins down to the wrist of his left hand, and about halfway down his back and over his chest. The severity of the injury caused a tremor in his left hand - his dominant one - that made it increasingly difficult to work. The veins were a bright red that looked like twisting flower vines, and had the circumstances of the injury not been so dire, he may have considered them something unique and - dare I myself say - beautiful.

Instead, he regarded them as his downfall. He grew weaker and weaker every hour. How he managed to continue on for the grand and debilitating total of three weeks, give or take a day or so, was a mystery to even himself. Determination, maybe. However absolutely cheesy that might sound, The Doctor was a stubborn man. He had a task and that very thing kept him running.

After a point, somewhere around the fourteen hour mark of the fifth day of the third week, he passed out. It felt as though someone had hit him over the head with a metal pipe, kicked him in the stomach, and kneed him where it counted all at once.

When he woke up, someone told him he'd been out for a whole month, which caused him to lean over the side of the ratty hospital bed he was lying in and vomit all the fluid the IVs had put into his system.

Once titles were given, they stuck. But after John had been given reports of everything that had happened in the war, he didn't want his. He didn't feel he deserved it in the least.

(Never mind, of course, that being nearly killed by a Dalek wasn't in any way his fault. Never mind that he was insanely loyal and...well, just generally insane. He blamed himself entirely for every soul lost and that was possibly doing more damage than the physical injuries.)

What happened afterwards was more than anything he could forgive himself for.

It was evident, distressingly so, that the Time Lords were losing. Their upper hand had been slapped away early on, and with The Doctor having been unavailable for such a long time, their troops were depleted. And he couldn't bear to watch any more of his people die.

To say it was a stupid decision was an understatement. It was a ridiculously and poorly thought through decision, and it was hastily and messily done. A time lock meant no time traveller could escape, but it also meant that the Daleks couldn't either. So he stole a TARDIS - punishable by death as of the second week of The Doctor's coma - and got out. He locked the planet. He thought he felt one of his hearts stop and wondered if maybe he would die after all. The TARDIS he'd stolen whirred in empathy and called him back to the controls, begging him to leave, to explore, so it could do what it was meant for even if The Doctor couldn't do what he was meant to anymore. He complied to his new home's wishes and limped back – because, sometime when he hadn't been paying attention to himself, he'd developed a knot in his right leg that hurt ridiculously - to his new control panel and made a little promise. Just under his breath, as he ran his hands over the buttons and levers. A promise to keep the last bit of his planet safe. He forced his hand to steady before he pulled the first lever, and then began his journey. And so he and she set off wherever she wanted first to go. And that was all he needed then. He had to get out and he had to heal and he had to leave everything behind him.

Which all lead to how he found himself on Earth nearly (if you were to record time in a linear fashion) 1000 years later.

He was on his twelfth regeneration, and he could honestly say this one was not a favourite. It was a short build. 5'6", and his limp made him look smaller, in his opinion.

He had a cane that he used when he was out and about. It took only 30 years to accept that the limp wasn't all there. Or, his mind wasn't, rather. Psychosomatic. Whenever his adrenaline was pumping, the limp tottered off and waited for a good hour to come back. His shoulder still throbbed and an occasional shock went through it. He could feel where his veins were lit up like a map in comparison to the rest of him. It looked as though a plant had grown through his bloodstream, and the skin was slightly raised and a bit warmer to the touch than everywhere else.

This regeneration had short, sandy blond hair, and it reminded him of so long ago when he was back on Gallifrey because it was undeniably a soldier's cut. His eyes were a dark blue and his nose was larger than he liked. Whenever he caught a glimpse in a mirror, he scrunched it up in disapproval. This regeneration had frown lines and no laughter wrinkles by his eyes. He wore jumpers and blue jeans and a tattered coat and he looked very soft, and very defeated.

As much as he hated to admit it, John believed that this regeneration better represented everything inside his head than regenerations previous. This Doctor was the true Doctor, old and worn and just so tired.

So it was half-limping back to his TARDIS that The Doctor looked up at the sky and smiled at the blue that matched his eyes, hardly aware of slowly growing pain in his leg, one hand clutched around the head of his cane and the other around his Sonic Screwdriver. And he was glad that the sun would remain because the people here, the people he'd saved singlehandedly, needed it. And if they had it, his task had been worth it.

He strolled leisurely through Trafalgar Square, admiring the way these people could interact without having to worry about being invaded. Not really knowing all of what was out there. Oh, the stories John could tell if someone asked. It had been a long time since his last companion. The loneliness was really only a constant reminder of what he couldn't do; he couldn't save anyone. His life was an endless circle of misery, conducting his guilt back at him from every angle.

He was just coming up to the door of his TARDIS, which had been sitting patiently in a less populated area of the Square, when a man came out from behind it with a compact magnifier, practically crawling about as he observed the wood.

"Er - what are you doing?" John questioned, shoving his screwdriver into his pocket.

"You can't just expect to drop a 1960's police box in the centre of London and have no one notice," the man said. His voice was lower than John had expected it to be and his tone was detached, as if he was disinterested in talking to John. In fact, he seemed entirely disinterested in anything but what was directly in front of him, and John quickly decided that he'd never met someone so entirely consumed and studious.

"I've done it before," John informed him. "And, technically, it's not strictly speaking in the centre."

The man jumped up with a swish of his black greatcoat and immediately moved forward like he was going to attack John. It triggered something in the old soldier's head and he shifted his cane up quickly to brace it against the man's chest.

He was a good head taller than John - something that tweaked a nerve in his mind - with dark, curly hair and extremely lanky limbs. His face was all cheekbones and bushy brows and his eyes were something else. They reminded John of the galaxy, such vivid and gorgeous colours all mixed up together. He looked unhealthily pale, like he'd been ill and not left his house for months. And he dressed like a posh git.

The man looked him up and down, not making to move away. "Psychosomatic," he said simply.

"I'm aware," John responded without missing a beat. "Who are you?"

"Sherlock Holmes," the man said, finally stepping back. He held his hand out expectantly. "And yourself?"

John eyed Sherlock's hand apprehensively before bringing his cane down and reaching out to shake it firmly. "I'm The Doctor," he said.

"The Doctor, not a doctor?" Sherlock inquired, letting his hand drop. "It's a title, then. What's your name?"

John blinked at the quick turn in the man's tone - it had gone from friendly to flat in seconds. "I go by The Doctor," he said, holding his chin up confidently. "You don't need to know any more."

Sherlock tilted his head and his eyes became completely analytical. Like he was a machine, built for the sole purpose of observing and processing. He snapped out of it a moment later. "This thing, this police box, it's yours, is it not? It's locked, and I've tried to pick it-"

"- you can pick locks? - "

"-with no success." Sherlock narrowed those eyes and the corner of his lips curled up. "It's not human. Not built by them, at least. Even a top government lock can be picked – trust me, I would know – so what is this? There's whirring inside as well, from what I could hear at the doorway. These boxes - even if it were human, and it clearly isn't - haven't been constructed in decades. The last was built in 1973. This is alien. You're alien; I could hear your heartbeat, coming so close to you before. That's irregular, too fast and too many beats in such a short time. Two hearts, is it, or three? Not to mention the tool I saw you put away - bit hasty for something you don't want to keep hidden, isn't it? Don't try to hide things from me, Doctor. You should know up front that it never works."

To say John was taken aback by such a quick observation was an understatement. He'd met geniuses before - brilliant, tortured people. This man was one. So quick, sharp - didn't hold back, either. Sherlock continued without letting John respond.

"Alien, then, but what are you doing here? Out for a little stroll? Come now, there has to be a reason." Sherlock paused and pursed his lips, looking John up and down again. John thought that maybe he was finally waiting for an answer, so he opened his mouth to speak, right as Sherlock went on to continue. "Stance, appearance, and reflexes indicate military. Cane, tremor, and nonexistent limp say ex-military under traumatic circumstances. Still doesn't explain why you're here, though. The tool you've hidden away suggests weapon, as does the - rather obvious - outline of a British Army Browning pistol stowed in the waistband of your trousers. You've picked that up here, then, haven't you? But what do you need it for?"

John had to snap his gaping mouth shut after the battering of little details and facts were shot at him in almost complete accuracy. "How did you do that?"

"Do what?"

"Tell me all of that - how did you know that?"

"I didn't know, I saw," Sherlock said, lip twitching with something akin to disgust. "You've not answered my question."

"Have a look inside?" John inquired instead of answering. "Curious person like you, I'm sure you'd get a kick out of it."

"What are you?"

"We can ask each other questions for hours and we won't get anywhere. I have all the time in the universe, Mr. Holmes."

Sherlock narrowed his eyes in obvious disbelief. "Sherlock," he said after a moment. "Call me Sherlock, please. I accept your offer, Doctor. In, then?" He gestured to the locked TARDIS and took a step away. John smirked and tightened his grip around the head of his cane, then snapped his fingers and watched what he assumed was a look of awe dawn on Sherlock's face.

"Go ahead," he said with a smile. Sherlock glanced at him with a grin that looked almost wicked and swept inside, not waiting for John to follow.

"It's bigger," Sherlock noted calmly as John hobbled in, shutting the door behind him. "Bigger inside, how is that possible?"

"It's a TARDIS," John informed him. "Grown on my home planet. Lots of...wibbly-wobbly intergalactic quantum physics talk that goes into explaining how this works."

"I am a genius, Doctor," Sherlock said with a scoff. He ran two spidery digits over a couple of the buttons on the control panel and leant over to look more closely. "I'm sure it wouldn't take very long for me to catch on."

"I'm not an intergalactic quantum physicist. I get the gist of it, yes, but I'm no expert. My title is 'Doctor,' after all. Don't tell me you haven't figured it out that far yet?" His tone turned teasing as he limped up the stairs to stand beside Sherlock.

"That part was simple," the man said distantly, looking with glistening eyes around the TARDIS. John could see how he was trying to control himself, to hide his excitement and fascination. "You've still not told me why you're here." He turned to face John with a look of expectancy.

John averted his eyes to the control panel and clenched his teeth as a shock passed through his torso. He huffed out a breath when the pain stopped reverberating through him.

"I'm here because... what else can a washed-up army doctor with a time-and-space-travelling machine do?" he questioned almost bitterly. "The answer is, not much." John shook his head and pushed away from Sherlock, walking around to the other side of the control panel. "So! Sherlock - where do you want to go? Anywhere in time and space are your options. That is, of course, if you'd like to accompany me somewhere. But we both know the answer to that question."

Sherlock grinned and sauntered over to stand by John. "How could I say no?" he asked. "And how can I choose?"

"How about we let her take us for a spin?" John pressed a few buttons and sidestepped to pull a lever and twist a knob. "Hold tight. I'm not technically qualified to drive this thing."

Sherlock's eyes widened and he opened his mouth to ask what John meant, but as the TARDIS started whirring more loudly, a big jolt knocked him off kilter and threw him against the railing. The expression on his face widened into an exhilarated smile as he grabbed onto the rail and he and John both started laughing without intentions of stopping.