Sherlock was watching the Doctor as he sat in his swing under the Tardis console making repairs. The Doctor hummed a merry tune, harmonizing with the mechanical hum of the ship. At his feet were many assorted tools, very few of which looked even remotely recognizable. There were also things that looked like nuts and bolts, but were really too different to be labeled as such.
On Sherlock's back was his backpack that they'd retrieved from his home earlier that day, full of clothes and his toothbrush. When he'd needed to wash his clothes, he'd had to wear some of the Doctor's old clothes, which of course were ginormous on him. They'd meant to get his things sooner, but they both tended to be absent-minded when it came to their own personal welfare.
"So Doctor, I was wondering," began Sherlock.
"Wondering is good," replied the Doctor without looking at him. He was wearing safety goggles that must have fit him at one time in his life but were now comically oversized.
"I've been with you for three weeks."
"Have you really? Linear time is so hard to keep track of. Unless I kept tally marks on the wall, I don't think I could ever keep up."
"And during that time I've watched you fly the Tardis," hedged Sherlock.
"I am a rather excellent driver, if I do say so myself."
"And after all that, I believe I understand it well enough to fly it myself."
"What was that? Didn't quite catch that last part."
"I want to fly the Tardis."
"You'll have to speak up kid, my ears aren't what they used to be. I'm such a golden-oldie."
"I want to fly the Tardis!" Sherlock yelled, getting frustrated.
"You want to fly her? You mean like a bird? Are you going to pick her up and fly her on your back? That sounds like an awful lot of work."
"No, I want to pilot the Tardis."
"The Tardis has no pilot, merely a humble guide. She doesn't let just anyone play with her controls, I'll tell you that."
"Let me fly your ship!" said Sherlock. If he kept this up he might just start throwing things at him.
"She doesn't fly, she disappears in one place and reappears in another. Kind of like a rabbit in a magic hat. If you don't even know that, how can you fly her?"
"I'm a proper genius, you said so yourself."
"I said that? I must be spending too much time in the time vortex, apparently."
"I'm not a Time Lord, but I'm plenty clever enough to fly your ship."
"Your call is important to us. Please hang up and try again."
Sherlock picked up a tool that almost looked like a monkey wrench, and threw it at his hands, completely screwing up his work. The Doctor brushed it off though and pretended it hadn't happened. Sherlock stormed back up the stairs to the console.
"Wait, come back! I'm not done ignoring you!" called out the Doctor with a laugh.
Sherlock held his hands over the console, wondering which button he would push first. He knew full well that he didn't know how to fly, and that he needed the Doctor's help. But the Doctor was very protective of his ship and didn't trust him to do it right, and so he wouldn't help him. Any other companion would have left it at that (no other companion would have even considered flying her, for that matter) but this was Sherlock, and once he decided he wanted to do something, by golly he was going to do it, especially when told not to. The Doctor had his chance to supervise and make sure he didn't mess anything up, but now he would have to face the consequences of ignoring little Sherlock.
He flipped a switch, and the Doctor called up, "Don't you even dare!"
This made him flip more even more switches and press more buttons. He'd seen the Doctor do it, he knew how to make it work. He just didn't know where they'd end up.
The Doctor left what he was doing as the mechanical wheezing noise of the Tardis sounded. He ran up the stairs to see what kind of trouble they were in.
"I swear, if you've flown my baby into a sun or a black hole I am never speaking to you again."
They opened the doors, and immediately they were both grabbed and hauled away by two lizard men.
"Nice destination," scoffed the Doctor.
"But I was able to fly her. I just wanted to prove my point," said Sherlock smugly.
"You always have to prove your point, don't you? Always have to have the last word."
"I have to have the last word? Last week, you let us get swallowed by a whale just to prove Jonah's story happened, and to prove that it is possible to survive for three days in the stomach of a whale. I had to smell nothing but fish guts for seventy-two hours straight. I will never be able to forget that smell, Doctor."
"Don't you dare judge me, Mister 'The world is round, I don't care what you say. You go ahead and burn me at the stake if you want, but I refuse to ever shut my mouth ever!'"
"It's the truth!"
"So what! They'll figure it out eventually. I don't like being burned at the stake for things that will work themselves out. We just barely made it out alive, that's the second time with you I've faced a burning."
"I think that was all your fault, Mr. Ginger."
"Don't mess with the hair. And my clothes still smell like smoke, thanks to you. I can't wear my fedora without smelling like a smoker."
"I had to wash mine three times before the fish smell came out."
"Silence!" the lizard men ordered.
They were both dragged into a control room. There were four other lizard people frantically working controls, and outside large glass windows they could see stars and asteroids. They were on a spaceship.
Red lights were flashing and an alarm was sounding. They were caught in an asteroid belt.
"A crashing ship, nice one," said the Doctor, though he wasn't really mad at Sherlock. In fact, he was rather impressed that an eight year old human understood the controls well enough to fly the Tardis, genius or no genius. Even if he didn't know where he was going, it was still better than any other human he'd seen, except for Donna and River of course. Thinking of them saddened him though, and so he instead pretended to be angry with Sherlock. He had to at least try to be a responsible guardian, after all.
"It's not a sun or a black hole. Count your blessings," replied Sherlock, obviously pleased with himself.
"We caught two stowaways. We don't know where they came from, but they came out of a big blue box of some kind."
"Who is the captain of this ship?" asked the Doctor.
"He's dead. Eaten from the inside out by space worms," said young-ish looking lizard. "He was the only one who could fly through an asteroid belt and come out alive."
The Doctor looked up at the lizard man holding him. "I can fly through the belt and keep the ship intact."
"You're just a child, you can't fly a spaceship."
"What have you got to lose? You're about to die anyway."
The two lizard men looked at each other uneasily, then released the two boys. The Doctor ran over to the man at the wheel. "May I?" he asked.
The woman steering ignored him, but then scraped the side of an asteroid. The force of it sent the ship heading straight for another asteroid. She threw hands up in the air and moved out of the chair, and the Doctor gripped the wheel and steered it out of the asteroid's way.
The Doctor deftly navigated his way through the belt. He made it look easy, but really it required great concentration.
The asteroids were getting bigger. The Doctor did many flips and twists with the ship to avoid them, but really he was just showing off.
They came upon an asteroid the size of a planet. The Doctor pulled up as hard as he could, his teeth gritted with exertion. He just barely skimmed it, and after that, they were clear of the belt.
The lizard people cheered, but the Doctor just tipped his hat.
"Thank you so much, human child," said the lizard woman who'd been trying to fly the ship. "We are forever in your debt. What is your name?"
"The Doctor, but I'm not human and I'm not a child."
The lizards all looked confused, but they quickly dismissed it.
"For saving the ship, we're making you our new captain."
"Erm, thanks for the offer, but I have my own ship to fly. Someone else is already trying to steal her," said the Doctor as he shot Sherlock a pointed look.
"We will make a deal with you. Pilot out ship until we reach our destination, and then you will be free to go. We do not have far to go now."
The Doctor shrugged. "All right then, I accept. May I see the coordinates of our destination?"
As the lizard woman showed the Doctor a computerized map of the system they were in, the lizard man who'd caught Sherlock before came to stand before him. He looked down at him disapprovingly.
"Are you of any use to us?" he asked in a deep, gravelly voice.
Sherlock stared up at him and replied, "If you're looking for hired help, you can take your search elsewhere. I don't work for reptiles."
"Sherlock," warned the Doctor as he studied the map. "If you can't say something nice, then shut the hell up."
"I will if they will."
"Play nice," he hissed.
The lizard man said, "If you serve no purpose, then oxygen and food rations will not be wasted on you. You will be ejected in one of the escape pods."
"Hold on," said the Doctor as he turned around and leaned against the wheel. "I'm the captain, and what I say goes. And I say he stays."
"Negative. The ship rules are that every member serves a purpose, or they are ejected."
"Then make him clean the toilets or something, but don't eject him."
"There is no position available, especially not for a rude child. He will be ejected."
"Wait one second," said the Doctor calmly as he reached into his pocket. He pulled out a silver key and tossed it to Sherlock.
"Is this a key to the Tardis? Does that mean you're giving me permission to fly her?"
"Good lord, no! Just hang on to it for now, and I'll catch up to you later, after we've landed. The ship will land in twelve hours, most escape pods have enough oxygen to last fifteen. I'll land the ship and then come find you."
"Sounds like a plan to me," said Sherlock.
"If I wanted my Tardis destroyed, I'd send it to the Daleks as a birthday present," muttered the Doctor under his breath.
The lizard man grabbed his arm and dragged him out of the control room and into a room with several escape pods, all of them just a few inches taller than Sherlock. He opened one of them and shoved him inside, and then closed it back.
The pod was small and cramped, but luckily Sherlock was not claustrophobic. He was jerked harshly when the pod was ejected, but then he felt nothing else but a light, floating sensation as he drifted through space.
He looked at all the flashing buttons and considered using them to try to control the pod, but eventually decided against it. Flying the Tardis was one thing, but if he accidentally opened the door, he would be dead in an instant; there would be no second chances.
Anyone else would have been mesmerized by the sight of billions of stars floating past, and overwhelmed by the sheer vastness of space. But to Sherlock, it was utter torture. The monotony of just sitting there with nothing to do, nothing to stimulate his brain, was almost too much for him to bear. He remembered the suggestion Mycroft had once given him for times like these: to work out complex math problems in his head. It only took the edge off his boredom, but it was still very maddening.
Several extremely boring hours passed before anything happened. He was banging his head against the side of the ship when something finally changed. He still felt like he was floating, but now he felt a tug, like a vacuum was sucking him in. The pod had no windows, but Sherlock realized that he must have drifted too close to a planet, and its gravity was now pulling him in.
He was going to crash land.
Over the next few minutes, he felt the pod moving faster and faster, until it crashed into the ground. Sherlock was thrown against its side, smashing his face into the wall painfully. He reflexively put out a hand to catch himself, and the force of the crash broke his right wrist, making him cry out in pain.
The door popped open on its own, and Sherlock crawled out. Every part of him ached, and he could feel his face bleeding. But other than the broken wrist, he was okay.
He stood on shaky legs and, while holding his throbbing wrist, looked around at his surroundings. When the pod had crashed, it had made a deep crater in the ground. No, that wasn't right. He was in a hole, not a crater. Light shone in from above, and he could see that there was a long catacomb leading from the pod. He doubted a pod crash could cause that.
With difficulty, he pulled himself on top of the tiny pod to the above ground. He bit his lip to keep from yelling from the pain of his protesting wrist.
The pod was spherical and smooth, not easy to climb on. Sherlock braced his foot against a wall of dirt and pushed himself up, and was able to climb on top.
Breathing heavily from exertion, he looked around. The sky was dark, but there was just enough light to see. He was in a graveyard that looked like it had been abandoned ages ago. In fact, the hole he pod had landed in was right by a headstone.
He gasped when he noticed the Tardis; it was humongous. It was as tall as a skyscraper. That couldn't be the Doctor's Tardis, but it looked just like it. Perhaps it was a monument to him. That made sense.
He got another surprise when he noticed the name on the headstone: River Song. So this was her grave. Why would the Doctor bury his wife in a place like this? Sure, cemeteries weren't supposed to be cheerful places, but this place was so dark and cold. If you were burying a loved one, you would do it in a nice place to honor them. This place was the opposite of that.
It occurred to him then that he hadn't seen a coffin in the hole. Maybe the tunnel he'd seen led to a special tomb, a final resting place befitting the woman the Doctor had loved so dearly.
Sherlock had a morbid curiosity to see where the tunnel led. Maybe the tunnel led to River's grave, or maybe it led to nowhere. Either way, he had some time to kill waiting for the Doctor. He might as well do some exploring.
He dropped back into the hole. The catacomb was dark and he'd need a light. There was a torch on the wall, but he didn't have any matches. He had been about to begin the arduous climb back to the surface to look for sticks to make a fire, when the pod suddenly burst into flames, sending a blast of heat into his face. He lit the torch and then wandered down the tunnel.
The walls were made of dirt and stone; they were all the same. But Sherlock was careful to spot and record the small differences of each one, such as the cracks and the spider webs hanging from them. It was important in case the tunnel branched off and became a maze. The last thing he needed was to become lost in another person's grave.
Several minutes passed, and he reached a metal door. It wasn't locked, but it was heavy. He pushed it open and then closed it back.
The walls were no longer made of dirt and stone, but of metal. He took this as a good sign and kept going.
He walked a good ways and then came to a flight of stairs. As he climbed them, he began to feel dizzy and lightheaded. He had no idea why. It had been several days since he'd eaten or slept, but he didn't think that was it. He'd gone longer than that before feeling anything like this. He shook his head to try to dispel the giddy feeling, but it only helped a little.
Once he'd climbed those steps, the maze started. Long hallways that led into more long hallways, and they looked so much alike that it was a challenge for Sherlock to spot the differences and keep track of where he'd been. He instead counted his steps one by one and recorded in his brain each time he went left or right if he needed to backtrack, which was often.
Wrong turn after wrong turn, but Sherlock didn't become frustrated like others might; he loved the mental challenge.
But as he marked each hallway in his mind, he realized that these halls were familiar. They were the halls in the Tardis, though older and dustier. He'd spent so much time just wandering the halls, exploring each room. The Doctor hadn't denied him access to any room, not even the one where he kept odds and ends from his past companions (he hadn't told him they were mementos of his old companions, he'd deduced it).
However, there were some doors that wouldn't open for him, no matter how hard he pushed and pulled, no matter how hard he picked the lock. At first he thought it was the Tardis' way of getting back at him for insulting her on that first day. But then he realized that the Doctor had probably asked her to, to keep him out of certain rooms. He'd considered asking the Doctor about it, but had decided against it. He'd let the Doctor keep the secrets behind those doors, because he had secrets of his own he had to protect.
These were the halls of the Tardis, but how could that be? He was underground in a tomb. Or was he? Maybe the catacombs had led to the Tardis monument. Perhaps River Song was buried there. Oh, how he wished there were windows, so he could look out and see for himself.
Right, left. Left, Right. Right, right, left left. Right, left, left, left, right, left right. It was almost dizzying, but he could almost sense his goal getting closer and closer. The vertigo had left, now it was just him and the rush of a puzzle.
He didn't know how long it took, the time had flown by, but eventually he reached a very large door without a handle. He pushed on it with all his strength, but it wouldn't budge.
Just when he had been about to give up and turn around, he noticed writing on the wall. Circular writing. Gallifreyan.
Three days after the pirate case, the Doctor had introduced Sherlock to his library. It wasn't the biggest library in the universe, but it came pretty darn close. Sherlock couldn't believe his eyes; there was so much knowledge, so much he could learn. And since the Tardis translated nearly everything, he needn't worry if a book was written in an alien language.
But not all of it was written. He discovered bottles holding spoken language. He had uncorked one and words rose into the air, words he could see and hear and even touch. He'd been careful to not let too much out, but he'd learned Gallifreyan that way. It hadn't required any effort on his part; the words just seemed to meld with his native tongue naturally. He wasn't exactly fluent, but he knew it well enough to read the words on the wall.
Here lies the Doctor: the man who slew more than anyone in history, who saved more lives than anyone in history.
None may enter his tomb, save those entrusted with the secret of his given name.
Here lies the Doctor: The god who wanted to be human.
"Oh. Not River Song's grave. His," said Sherlock to himself. That realization led to another; he didn't know how he knew it, but he realized that what he was standing in wasn't a monument to the Tardis, it was the Tardis.
At first he didn't understand, but the more he thought about it, the more it made sense. The Doctor was a time traveler, an ageless god, but not immortal. He would have to die somehow, someday.
"That means my grave is out there, too."
The thought of himself lying dead somewhere in the future didn't disturb him like it would have anyone else. Death was part of life; undeniable, unbeatable. Avoidable for a time, but never inescapable. It was the one mystery that could never be solved. He didn't want to die anytime soon, but the idea didn't scare him.
Sherlock wondered why on earth the Doctor would want to be human. Humans were so limited, most of them were idiots. Wouldn't it be better to be a god, to be respected for your intelligence and power? He certainly thought so. The Doctor was so strange.
Now, when the Doctor had shown him the library, he'd told him he could read any book he wanted, except one: The History of the Time War.
Sherlock had of course protested. "You just banned the coolest book in the whole library."
The Doctor had replied solemnly, "There is nothing cool about that book. This library contains at least one copy of every book ever written, and some of them are the original documents. Well, it has the ones I like, I get rid of the duds. You can read all of them, but not that one. If you read it, there will be consequences."
Sherlock had weighed his options to decide if he would respect the Doctor's wishes or not. That book must contain great secrets, and the Doctor's greatest secret is his name, and so his name must be written in there somewhere. In the end, Sherlock decided not to read the book, but to instead deduce the Doctor's name.
He'd learned Gallifreyan from the bottles, and from there had read many Gallifreyan and Time Lord books and scrolls. It was a good thing too, because the Tardis didn't translate Gallifreyan.
He learned all about Gallifrey's history and customs, and he'd read how young Gallifreyans became Time Lords and Time Ladies. All he lacked was the Time War, but he resisted the urge to read the book so as not to cheat.
After learning the language and reading the books, he felt sure he knew his name. He'd made sure not to tell the Doctor. He didn't know how he would react if he found out he knew the language, or if he knew he had deduced his name, but just in case he kept it to himself.
It didn't seem like such a big deal to him. What was so important about it? Sure, it was strange, but what do you expect from an alien name? Why was it so important to him to keep it a secret, he wondered.
Softly, in case anyone was listening, he whispered the name. As he spoke it, he knew he might be incorrect. He didn't know what he would do in that case, but it didn't matter. The doors swung open on their own, and Sherlock entered inside.
His eyes widened and his mouth hung open slightly when he saw what was inside. It looked like the console room of the Doctor's Tardis, but vastly different. Wild ivy grew on the walls, like nature was in the process of taking over. Instead of the time rotor and console, there was a bright tangle of shining white energy tendrils, swirling and writhing in a column.
Sherlock walked closer to the tendrils, unsure of what to make of them. He was tempted to touch them, to see what they felt like, but something told him it was a bad idea. He took a step back from the tendrils, and saw something behind them. A skeleton.
It was the skeleton of a man. He was fully dressed, with his hands clasped on his chest. The thing that really stood out to him was that it was a man lying here, and not a child.
"He'll have at least one more regeneration. He won't die a child. I'm sure he'll be happy about that," Sherlock mused.
He felt a strange feeling in his chest, one he wasn't really familiar with. What was it? Sadness? He didn't think so. Depression? Nope.
He looked in his mind palace for something to go on, because he didn't know what to do about this feeling. He had catalogued all the emotions he'd seen on other people's faces to be used to read them. He didn't really understand why people felt the way they did, or how to help them, and he most certainly didn't know what to do when he was the one dealing with them.
After checking his mind palace, the conclusion he came to was that he was grieving. Grieving his only friend's eventual death. Vaguely he wondered how he'd died, or if he'd been alone. But what did that matter? No matter the circumstances, the outcome wouldn't change.
He eyed the skull. He'd always been interested in the human body; how it worked, what made it tick, how it reacted when introduced to different chemicals. So of course he was curious about the body of a Time Lord. It looked exactly like a human skull, but were there differences beneath the surface? He wanted to study it, to understand it.
Now, Sherlock tended to be rather impatient and impulsive, but even he could see that what he was about to do was wrong on so many levels. Still though, he just couldn't resist. He took the skull in his hands and looked at it more closely. He couldn't leave it here, not in this awful tomb in this dark, wretched graveyard. So he took off his backpack and gently put the skull inside, and then zipped it back up.
Sherlock justified it by saying that he wanted to study it, to learn more about Time Lords. But in reality (and he would never admit it) it was the only way he knew to cope with these new, unfamiliar feelings. It was the only course of action that seemed to alleviate the grief. The Doctor was the first person to see any value in him, the first to be proud to call him friend. It was annoying when he laid down the law, but for the most part he let Sherlock be. He didn't force him to eat or sleep (though when enough days passed without either one, Sherlock would find food and pillows lying in random places). He wasn't afraid to be himself; he tried to act more grown up to compensate for his youthful appearance, but he wasn't afraid to act like a kid and encouraged Sherlock to do the same, instead of acting like an adult like he so often did. He didn't tell him what to do or try to control his life. He never judged him and his weird habits; he was content to just take him on adventures and have fun.
And so the thought that one day he would lose his only friend upset Sherlock in more ways than he realized. He'd never had a friend before, and so he didn't know how to say goodbye. He hated the very thought that the Doctor would die someday, even if that day wouldn't come for a very long time. He couldn't bear the thought of leaving the Tardis and going back to real life where no one cared about him. It didn't even matter to him anymore that none of this made sense, because for the first time in his life, he was truly happy. But this tomb told him that it would all end one day.
Sherlock was just a child, no matter how grownup he appeared to be at times. And so even with such a brilliant mind as his, he didn't always make the best choices. He took the skull, and then fled back out the door. As he ran, he heard the doors close again with a loud thud.
He had to get out of there quickly, before the Doctor discovered him there. He didn't know what conclusions he'd come to, but he couldn't risk him finding out the truth. He'd never forgive him if he ever found out what he'd done.
He ran back through the corridors, retracing each step in his mind. It wasn't long before he found and descended the staircase that led back to the dirt and stone catacombs.
He found the pod and scrambled back up on top of it, ignoring his swollen wrist. He climbed out of the hole and got as far away from the pod and the giant Tardis as possible.
He slowed down when he could no longer see River Song's headstone. He had to catch his breath after all that running. There was always so much running on these adventures.
He leaned against a large headstone to rest, and as he did the Tardis suddenly materialized in front of him. He jumped as the door opened and the Doctor stepped out.
"Hidey-ho! Had fun, Sher-" His mouth formed into an O shape when he saw where he was. "This wasn't where you were supposed to land."
"Where was I supposed to land?" asked Sherlock, trying to hide his guilt under a blank expression.
"There's a planet right by this one with the biggest and fastest roller coaster in the universe. I thought you'd end up there and you could have some fun for a bit while you waited for me, but I see that didn't really work out."
"Not really, no. But what is the name of this planet?" asked Sherlock.
"Trenzalore." By the way he looked, Sherlock wondered if he knew his grave was here. What would that be like, to know where your grave was, to be able to see and touch it.
"How did you find me here?" asked Sherlock.
"The key I gave you. I recently installed a tracking device in it so I can find you. It's also slightly psychic, like the psychic paper, so you can call me. If you need me, if you think about me, I'll be able to find you."
"Did you do this for your other companions?"
"No. But I already told you, I won't tell your mother you died in my care. You're too important, I'm keeping you safe.
"We should be going," said the Doctor as he stepped back into the Tardis. "There's nothing to see here, nothing at all."
"Okay," said Sherlock as he followed him into the Tardis.
The Doctor noticed his wrist. "Ouch. Did that happen in the crash?"
"It's all right. It doesn't hurt so much as before."
"Don't be a hero. Just say it hurts," said the Doctor as he took off down a corridor. He called out over his shoulder, "I'll be right back with some medical supplies."
He returned a moment later and had Sherlock sit in the swing that he usually sat in to repair the Tardis. Tenderly he took Sherlock's wrist and examined it.
"It's cracked all the way through. It'll have to be adjusted." He pointed over Sherlock's shoulder and shouted, "Oh my God, what is Mycroft doing on my ship!?"
There was no way Mycroft could possibly be on the ship, but it took him off guard and he looked anyway. When he turned his head, the Doctor harshly jerked his wrist with both hands to reset it. Sherlock screamed in agony, and tears leaked from his eyes. It was worse than actually breaking it.
"Sorry," said the Doctor as he wrapped a bandage around it.
To distract himself from the blinding pain, Sherlock tried to make conversation. "I didn't think you were this kind of doctor."
"I have many hobbies," he replied with a shrug.
Sherlock couldn't think of anything else to talk about. All he could do was worry that the Doctor might look in his backpack, or somehow sense that his own skull was hidden on the ship.
"Are you hiding something from me?" asked the Doctor.
"No, why would I?"
"You have an almost perfect poker face, but I know the look in your eyes. I used to see it all the time in my own kid's eyes. It's fear of being caught when you know you're in trouble."
"You had children?" asked Sherlock in an attempt to distract him.
"Once, a long time ago, but we're not talking about them. We're talking about you."
"I hate it when you go all parent-mode on me. Is that why you do it, because I remind you of one of your children?"
"No, you're my friend. I do it because you remind me of myself. You need someone to look after you, to make sure you don't go too far and keep you out of trouble. You don't realize it, but you've been doing the same for me. You live in darkness, but you have a good heart. I live in the light, but there is darkness in me that always threatens to overtake me. You and I need people in our lives to bring out the light and keep us out of trouble. Later in life you'll meet people who will do a far better job, but for now you'll have to settle for me."
"What do you mean, I'll meet people like that?"
"That's not important right now. But what is important is what you're keeping from me."
"You keep plenty of secrets," Sherlock pointed out.
"Only to protect you. Does your secret protect me?"
"Yes and no. I guess it's more to protect me."
"Please, feel free to divulge. I won't stop badgering you until you do."
Sherlock was cornered. The Doctor meant what he said, he would not give up until he got the truth. So Sherlock decided to divulge another secret, the lesser of two evils, the one he assumed would get him into far less trouble.
"I know your name."
The Doctor's eyes widened. "Did you read the Time War book? I specifically said-"
"No, I didn't touch it. I figured out your name by using the bottles and reading Gallifreyan texts, and I used what I know about you. Your name is-"
The Doctor clamped a hand over his mouth. "Listen very carefully, Sherlock. I can take away your memories of my name, make it so that you never remember that you ever knew it. But I won't, on the condition that you promise to never speak it."
"Why is it so important? It's just a word."
"It was once just a word, but not anymore. Allow me to explain."
He finished bandaging his hand and wrist and then helped him into a sling. He then left for a moment and came back with a notebook and a pencil. He hid the notebook from Sherlock and drew something, and then held it up to show him.
"This is Old High Gallifreyan. But what does it look like to you?"
"The insides of several clocks."
"Exactly. Time Lords literally wrote with time. The words possessed the power to raise empires or destroy gods. Names became very powerful; the more the Time Lord did, the greater his name became.
"After all I've done in my life, the impact I've made and the scars I've left behind, my name has become the most powerful word of all. Thrown around willy-nilly, the consequences could become catastrophic."
"You're name is your timeline," mused Sherlock. "So saying it reveals everything you've ever done."
"Yes, there's that too," he admitted gravely. "But now do you understand? Can you promise you won't ever say it?"
"I promise." Technically he'd already broken it, but that was a minor detail. And it wasn't like he had much choice; it was either promise or have his memory of the word erased. It was an easy decision.
Sherlock looked at the circles. These words hadn't been used in the books he'd read, and he couldn't make them out.
"Is this your name?" he asked.
"No. This says, "Want to get some pie?"
Sherlock hadn't eaten in nearly a week, and so he wouldn't mind a meal. "Sure," he replied.
"Great," said the Doctor, becoming more animated. He took off the fedora he always wore and put it on Sherlock's head. "There's this shop on earth that has the best pie you will ever eat. They mix up their flavors in such weird ways, you'd think it'd be gross but it's actually delicious. You have to try the chocolate-blueberry, it's to die for."
The Doctor transported the Tardis to the shop, all the while talking about the different pies. His enthusiasm was contagious, and Sherlock felt his spirits lift.
But as they exited the Tardis and made for the shop, Sherlock wondered if he should feel guilty for deceiving his friend.