Author's note: And thereby I proudly proclaim Bingo, my friends. This trope: AU: Space. Sci-Fi fan here, so I loved writing this. Enjoy!

Sherlock Holmes hadn't continuously stayed on Earth for more than a few days in the last five years.

There had been tests, psychological as well as medical exams, the Ministry for Outer Affairs had become involved, but he was healthy and he chose to work in space, and there was nothing they could do about it. His brother Mycroft made sure of it. Sherlock briefly wondered if he was glad that he was gone from Earth, but it didn't matter.

What mattered was the work.

Exploring new areas of space, of this world that wasn't limited like the one he came from, but kept expanding, the hyper drive he had helped invent pushing him farther and farther between the stars, he sitting at the controls, doing experiments, alone, finally alone.

He had never felt as free on earth as he felt here, surrounded by darkness. Now and then he reported to the Ministry. They never asked many questions and always accepted his findings without waiting for proof. They knew he was good.

He was the best explorer they had ever had, and he would continue to be so. When he stayed on earth, he was at the station, waiting for his ship to be looked over and declared to be fit for service, which it always was because he, other than the other idiots who called themselves explorers, made sure it was in perfect shape. He knew every nook, every noise it made. He knew when to get into his space suit and repair something.

Currently, all was well.

He had just travelled through a galaxy that possessed two suns and several inhabitable planets and had recorded the fact just like he did everything else.

Now he was looking at a red planet, not unlike Mars; the atmosphere was more condensed, however. After a few initial tests done from his ship, he put on his suit, whose inside pressure he had carefully adjusted so it would fit the atmosphere and went through the air cabin, setting foot on the planet.

He already knew that it was inhabitable for humans, at least without a lot of construction to be done. They would never be able to walk on the surface without suits. There might be minerals and other valuable substances, however, and he took some samples before moving forward.

He hadn't seen any life forms during his flight over the planet; his ship would be safe enough.

According to his instruments, the planet was slightly smaller than earth. After he had walked a few miles, eventually circling back to the ship, taking samples, he decided to land on a different part. The temperature was minus 160°; he had landed near the equator, so it must be even colder on the other parts of the planet. Parts, not continents – there were no oceans, no lakes, no rivers, as far as he could tell.

He flew to what he would have called the South Pole on earth, the hyperdrive taking him there in minutes. He finally found evidence that this planet was not totally inhabitable – big, slowly moving life forms that resembled polar bears. Sadly, they were too big to take one with him, but as he watched them from a safe distance, he came upon a dead one that couldn't have expired more than a few hours ago, and he took a sample.

He spent several hours in the ship, experimenting. The ground contained a lot of iron and traces of zinc. There was little to no moisture in the atmosphere. There was no sign of water in the earth. The animal was more interesting.

Its skin was of a subdued red and unusually dry. In fact, his cells contained almost as little water as the atmosphere. Decomposition hadn't yet so far advanced to explain it. These animals must live without water for an extended period of time – maybe they never drank at all. It was possible the consumed what little liquid they needed through their leathery skin.

Sherlock regretted that he couldn't take the whole body with him; maybe he could convince the Ministry to send a bigger ship and catch one or more of the animals alive. The information they gained might be useful, considering there were many countries that had too little water and too many thirsty people.

Too many people – it was one of the reasons Sherlock preferred living here, in his ship, isolated. He could tell everything about a person by looking at them; but at this age, when almost every city one earth was overpopulated, a walk down a street consisted of information after information flashing by, suffocating him.

He looked at the miles he had travelled during this mission and sighed. He'd been gone for seven months now, and it was time to return to have his ship checked. It didn't matter that he always had 221B under control, that he felt it when a bolt got loose – he still had to go.

He comforted himself that he would be back in space within a week.

Only that he wouldn't.

When Mycroft gave him the news, he all but screamed, "But there is nothing the matter with 221B!"

"Sherlock" his brother answered, calm as always, "This isn't about your ship. The Ministry has looked through your mission protocols. You haven't stayed one earth for longer than a week in years. During this time, you never left the station. It is feared you will develop mental problems – "

"I will if they force me to stay here for six months".

He forced himself not to show Mycroft how upset he was. Cities. People. Millions upon millions of people. Information pushing him down, making it hard to think –

Maybe he could go to the country. Lie low for six months.

Mycroft anticipated his question and shook his head.

"No, Sherlock. You are to live in London".

London. They had grown up there, but Sherlock had never been prone to nostalgia.

"There will be people".

He didn't care that he sounded like a petulant child.

"That is the point".

He wanted to protest, but one look in Mycroft's face convinced him not to. He knew this expression. There was nothing he could do. There was something like worry there, too, and it was unfamiliar enough to make him agree.

The flat was quiet and not to fancy, and Sherlock decided that he could stay here for six months. He would have to engage in human contact, however, since the Ministry wanted to make sure he was "fit for service" when he boarded his ship. As if human contact would help him be fit for service light years from here, with only space for company.

Mycroft suggested getting a roommate, but Sherlock refused. He was not to be subjected to the presence of a human being in the one place he could find peace during these long months.

As he pointed out, he had a landlady, which counted as social interaction. Mrs. Hudson had decided that he must be lonely after all these years "out there", and that he certainly hadn't had a home cooked meal in a long time, and was constantly coming up to ask if he wanted anything, if he'd liked the tea, whether he had dusted, because the state of the place –

It was a miracle he could stand her. But somehow, her motherly nature was making it difficult to be annoyed.

At night, he looked at the sky and thought of the planets that were still undiscovered, of the many that must as this moment come into existence. Six months, and he would be among them.

Because he knew Mycroft would keep him under surveillance, he went out several times a week, usually when he's used up the samples he distracted himself with. He knew there would be new ones when he returned. The Ministry might not want him in space, but they still needed his expertise.

It was difficult, making his course through the many people who all rushed God knew where. He still remembered every street in London from his childhood, and he could find quieter roads, but there were people everywhere, laughing, crying, living, flaunting all there was to know about them right in front of his eyes. And yet he was the only one who knew. It was frustrating.

They never stood still long enough for him to absorb. If they would only move slower –

At least he was walking around, so the Ministry couldn't claim he had holed himself up for six months.

One day, he found someone who moved slowly.

He hadn't expected it, and he certainly hadn't looked for anyone who did.

But he was walking down the street that led to St. Bart's. Just as he passed the door, it opened, and two men stepped out.

One of them wore glasses and was overweight.

Teacher. Has a girlfriend. Likes reading.

The information passed by without meaning anything, because Sherlock was looking at the man the teacher was smiling kindly at, the reason the teacher moved slow enough for him to deduce.

He was limping, leaning heavily on his cane. He was pale, and there were dark circles under his eyes. He looked defeated. But –

The way he holds himself. Military. The teacher is an old friend of his, this much is clear by the lack of personal space between them. School friends. Trained at Bart's. Army doctor. Invalided home.

Just as the teacher was saying, "I am sure you will – " Sherlock blurted out, "Iraq or Afghanistan?"

He had long ago stopped to pay attention to news from earth, but he recalled there were two wars going on where an army doctor could be wounded in action.

The man stared.

"Afghanistan. How – "

"Deduced you" Sherlock replied courtly. If the man couldn't understand, he would walk away. They always did.

"What – "

The man broke off, clearly torn between his curiosity and being polite. Sherlock had never been patient with polite people.

"Goodbye" he said, turning around.

"Wait!"

He didn't know why he stopped. The man came after him, faster than before. His limp wasn't as bad.

Psychosomatic.

"What's your name?" the man breathed.

Sherlock should have left without a word.

In any other situation, he would have.

But he said, "My name is Sherlock Holmes. The address is 221B Baker Street" and quickly returned there. Mycroft had no doubt found it amusing to give him an address just like his ship.

He didn't know why he had given it to the man, and he didn't think it would lead to anything.

But that evening, there was a knock on the door.

He was busy looking through a microscope and called out, "I don't need anything, Mrs. Hudson", but when the door opened and he heard the thump of a cane, he looked up.

The man from this afternoon stood there, looking awkward.

"You still owe me an explanation" he said finally after they had started at each other for several moments.

Sherlock decided he might as well give it to him. People fled when he did. They told him to piss off and left.

The man did neither.

He looked at him with big eyes and said, "That was amazing".

Sherlock stared. Looked at the microscope. Stood up. Went to the man and held out his hand.

"I don't know your name".

"John Watson" he said, and they shook hand.

John stayed for hours. He wanted to know more about Sherlock. He told him about his job. The doctor was fascinated. Sherlock learned that John had a sister he wasn't close to, and that he was looking for a flat, but that it wasn't easy to find cheep accommodation.

He bit his lip and looked around.

Just as John was rising to go, he said, "You could live here. I have been told it would look positive on my report if I had a flatmate".

"I – really?"

He knew John would say yes just from the happy glint in his eyes as he looked around the flat once more.

He moved in the next day.

Mycroft came by immediately.

"What?" Sherlock asked him while John was unpacking, not yet aware that someone had entered their flat. "You suggested it".

Mycroft shot him a long, calculating look, then nodded. He stayed long enough to be introduced to and to try to intimidate John – Sherlock could hardly hide his mirth when he failed.

Living with John turned out to be surprisingly easy.

He tried to get him to eat and sleep more than was necessary, but he didn't bat an eyelid at his experiments and he didn't say anything if he played his violin at night – it had been so long that he had played it on earth and not in the velvet dark of space, so that it was new to him that he had someone listening.

When he saw Sherlock stare at the night sky by the open window, he asked and Sherlock told him, told him about the beauty of the nothing called space, of the stars that shone stronger and stronger the further away from earth one got, of planets were the laws of physics were overturned, were strange animals crept through swamps, were life forms he couldn't even describe attacked his ship before he could set a foot outside.

"Sounds dangerous" he said.

"It is" Sherlock answered.

John looked at Sherlock and followed his gaze up in the sky and said nothing.

After a few weeks of this, Mike Stamford – the teacher – came to visit. He introduced himself – and Sherlock found to his surprise that he didn't mind talking to him. He was always friendly and didn't pay attention to the strange noises that came from the kitchen. He asked about his deductions and Sherlock told him everything he knew about him, John confirming that he hadn't told him.

He was impressed, even if he didn't praise him as much as John had.

A few days later, he brought a trembling woman.

"Molly Hooper" he introduced her. "She works at St. Bart's. She wants to know – "

"If her boyfriend is cheating on her" Sherlock finished. "Yes. And with a man".

He had expected her to cry, but she thanked him for the information. She had just wanted to be sure, she said.

From this day on, more and more people came. First acquaintances of Mike Stamford and Molly Hooper, then it slowly became known – especially through the website John made him set up – that he could deduce people. At first, he solved petty problems; a lost wallet, a broken heart, a missing dog. Then he became involved with finding someone's will, proving that one's uncle was lying in a process, and eventually people who felt the police didn't take their case seriously came to him.

It wasn't much, really; forgery, petty theft – but then a man came to them whose teenage daughter had disappeared. The police believed her to be a runaway.

Sherlock took the case and a few hours later he and John were fighting against the kidnappers.

Luckily, John's aim was as good as it had been in the army. Sherlock found out when one of the kidnappers held a knife to his throat.

It was obvious that the police were less than pleased. All officers, that was, except for one man, who introduced himself as DI Lestrade. He thanked him.

Sherlock wasn't used to being thanked. He didn't know how to react.

Four months after he had left the station, three months and two weeks after John had moved in, the DI came to their flat and asked for help.

From then on, the days were filled with chases and criminals and evidence, aside from the concerts and talks about space that had already been there, and when Mycroft called him to inform him that he could go next week, Sherlock didn't believe that six months had passed.

He looked up at the sky. The call was as strong as always. He knew he would leave.

But for the first time, he would leave someone behind.

When he hung up, he heard movement behind him. John had entered the living room while he had been talking.

He turned around.

"So you're going".

It was a statement. Sherlock nodded.

John went into the kitchen and made tea.

Sherlock came to a decision. Sometime between looking at the sky and hearing John take a much longer time to make tea, he came to a decision.

"The missions – " he said. "They are usually between five and six months long".

John came out of the kitchen with two cups. He waited for him to continue.

"And normally, the explorer stays on earth for a few months afterwards. Something about mental health".

He spit the words out, and John smiled.

"I thought I might do the same".

He waited until John understood – understood that he would come back and live half a year in Baker Street, continuing his job as a consulting detective (as he himself had decided to call it) before leaving again.

John's smile grew wider. Sherlock continued, although he wasn't sure if the doctor would react as positively to his proposal.

"Provided, of course, that I do return. As you recall, I have often barely survived certain situations..."

He waited for the affirmative.

"This one planet – there are animals who don't need water to survive. They are as big as polar bears. Strong and fast. I'll need a bigger ship and help to catch one or two".

When John didn't answer, he added, "Could be dangerous".

The doctor looked at the floor, then past Sherlock out the window, at the sky.

He didn't answer. But his gaze slowly swept to his face and he gave a firm nod.

Then they smiled.

A week later, they boarded the bigger ship Mycroft had had built. Sherlock immediately realized it consisted in a large part of the familiar controls and machines of 221B.

For the first time, he turned around to his brother and waved before the hatch closed.

Mycroft nodded.

John took his first start in a rocket ship with remarkable ease.

"I'm with you" he said. "I don't scare that easy any more".

And as they glided through the stars as a team for the first time, they laughed.

Author's note: I hope you liked it, please review.