Christmas night. The 221b door numbers, polished to shine today, softly reflect the light of the street lamps. Below them, somebody (presumably not the same person who cleaned and polished all the metal parts) has pinned a note to the door with a jackknife I recognise as my own.

Sherlock Friends meeting.

(Drawing of a smiley face with a Santa hat.)

Anybody who sympathises and their family members are welcome.

It is the third time I see this, but the term family members is new.

The door is ajar. Judging by the smell, Mrs Hudson has spent the whole day baking biscuits. A considerable amount of them was left in the oven for too long and burnt to black. It happened between 1 and 3 pm, which is evident by the fact that the scorched crumbs around the bins are widely distributed, but not covered by fresh snow. Snow stopped falling at 12:48.

She also made pudding, roast goose and potatoes. Some unskilled person tried to help her in the kitchen and messed up the sauce – it smells like cinnamon chewing gum. Must have been the same person who, I think, put salt instead of sugar in the final portion of biscuit dough.

The house is rather full today, I can hear a lot of talking and laughing and glasses clicking against others. There must be more people inside than in the past two years.

A few Christmas tree needles are scattered across the doorstep, frozen into the thin layers of snow. Picea abies – oh no, who chose that one? Two … no, three people must have been here this morning to bring the tree in. They were in bright spirits and a bit too careless, for it left some tiny scratches on the doorframe.

This is home. I should not be here. I'll only stay for a few minutes, stepping a little closer to warm my face in the air draught from inside. My breath fogs up the polished metal as I exhale. The "b" had to be replaced last year after some kid had stolen the letter and probably kept it as a trophy. The door plate of the scary Mr Holmes. A funny thought. I take my right glove off and touch the door knocker. It feels very cold. It shifts a little, making a faint scratching noise. Nobody in the house will hear it. Nobody will recognise the footprints I leave on the doorstep. I am not even invited to the party obviously, since I am neither a friend of mine nor a family member of theirs, so I guess it is better this way.

Three years ago, I left the country and moved to America. My brother had contacted the government and found a secret military base from where I could operate without anyone discovering my survival of the fall. The base is located in the north-eastern part of the USA. New England, they call it, but it is nothing like England at all.

They have me working for the FBI. Mycroft arranged for me to be hired without even having to pass their lie detector and drug tests. They give me riddles to solve, codes to break and behaviour patterns of public enemies to analyse. At first, it looked paradisical. Hundreds and hundreds of cases to solve. Bomb threats, terrorist attacks and many other exciting crimes. Being busy every day, never getting bored, without even having to move because it all works with an encoded web connection and a tap-proof phone line. The room they had prepared for me in the base was small and barren, but I thought I could try and make myself at home there. I'm still trying.

The Americans pay me well – a lot of dollars I can't do anything with. I do not need much. I even eat my dinner in the mess hall. All I need is coffee powder, tea bags, clothes and a few other little items. I pay one of the soldiers to buy them for me. Going out in public still holds the danger of being discovered, and I don't go out for walks like other people do. Green grass and colourful trees do look pretty, but after all it's a useless waste of time.

One day I woke up and realised that I had cried in my sleep. My face and the pillow I had rested my head on were wet. That was unusual. After a cup of tea for breakfast I felt better, but still strangely agitated. My hands were shaking. I nearly spilled the milk. Looking at the London calendar on my wall (at that time showing a picture of Chinatown), which I normally found calming, only made it worse this time. So did the sight of the Union Jack cushion on my bed (which Mycroft has nicked from the flat for me and brought over on one of his visits) and the print of Vermeer's The Astronomer in the hallway (which suddenly reminded me of the Hickman Gallery). After a few hours of this exceptional state, I concluded that I must be homesick. Nothing to seriously worry about, only the symptoms of a severe adjustment disorder. Having sorted this out, I was quickly able to regain control over myself and supress my emotions as usual. Mostly. At least enough to make sure that none of the soldiers and Special Agents I regularly encounter in the base noticed any change in my behaviour. They talk about me when they think I'm not listening. They say I am made of ice, just like my brother. I wish they were right.

Inside 221b, they are starting to sing "We wish you a merry Christmas" now. One voice does not join in. But you must be there, aren't you, although you don't live in this place anymore.

Shortly after I had left England, Mrs Hudson had the flat converted into a museum. The Sherlock Friends created a fund to keep the rent paid so no strangers would have to move in, and a few months later it was opened to the public. My brother sent me a few photos of the exhibition. Old photographs, partially donated by Mycroft, and press articles are stuck all over the walls. The wallpaper is barely visible anymore, only the part with the smiley and the bullet holes was left uncovered. A few chemicals and Petri dishes are arranged on the kitchen table, containing the remains of my experiment on postmortal hair growth in cats. They even keep body parts in the fridge, made of wax. With increasing receipts, they turned the former rent fund into a charity organisation supporting underprivileged children who want to study forensics. They assumed that would be in accordance with my wishes. Well, why not. All in all, 221b is a busy place currently. Charity and fundraising events regularly take place in there. Not on Christmas Eve, though. Christmas is reserved for the people I worked with, who knew me best and still believe that Moriarty was real and I was not a fraud. There are very few of them, but they seem to have multiplied over time. My brother regularly keeps me updated on that. Molly has a new boyfriend, a straight one this time. Today he is apparently trying to impress her by wearing a particularly expensive brand of aftershave, the scent of which is still lingering in the entrance. Well, the trainers he is wearing, judging by his shoeprints in the snow, should have told her by now that he is not that rich. Lestrade is newly married to the owner of a sports goods specialist shop with five children of her first marriage. John is married, too. His wife is pregnant.

One of the soldiers in the army base is not as avoidant towards me as the others are. A young man who has just started his military career and never been anywhere else than in the base and his hometown in Colorado. I can't recall his name right now. In my mind, I always refer to him as not John. He sometimes sits down at my table in the mess hall when his friends are absent. It's nice to have company, although we don't get along too well. He keeps making small talk, my capability of which is rather limited. I'm not allowed to talk about my work, since it is all top secret, so I mostly remain silent. He tells me about his friends and family, where he used to live and how he grew up – incredibly boring – and what it is like being a soldier. The latter topic is especially annoying, for I already know a lot about it and I don't think he does.

Once I told him I would like to go back to England, just to converse. Homesick, eh? he grinned. Yeah, yeah, I would go back to Colorado, too, if I could. It gets lonely up here. He then suggested that I should take a break and go out and have some fun, man! With his army pen, he wrote down on a napkin the address of a house of prostitution in a nearby village.

I went there. Disguised, of course. Not masked or anything, just hiding in plain sight. Perhaps I was hoping to meet someone of Irene's calibre.

The address led me to an old shed in the backyard of a run-down building. According to the flashing red neon letters above the entrance door, it was called the Flying Night.

Inside it was stuffy and exactly as shabby as it had looked from the outside. As soon as I walked in, I had a woman clinging to my jacket, whispering, Hey, sweetheart, you look pale. Don't you want me to fix that? She stroked my cheek repeatedly with her left index finger. Her latex clothes smelled of cheap perfume – probably an imitation of Dunhill Desire – and Luckies smoke. Her pinpoint pupils were staring right through me and her hand was shaking. The only one of us who badly needed a fix was her. Her lipstick was smudgy and she was chewing two sticks of Big Red to obscure the fact that she had thrown up shortly before. I'll show you how to fly, darlin' … She was even paler than I am and anorexically thin. The white of her eyes was beginning to turn yellow from jaundice. I'm not a doctor, but I would have bet on hepatitis A. Do ordinary men find that attractive? I don't. I pushed her away, gave her a hundred dollar note just to make her leave me alone, and immediately left the Flying Night, asking myself if life would be more fun if I was less observant.

After that event, back in the base, I made myself another cup of tea and decided to go home for Christmas. Everybody does that, it's normal, and it would be my present. There does not have to be more than one visit, I thought, just this one year. I was wrong, I must admit. I will always come back, every year, driven by an incurable illness: I miss it. London is cold in winter, but it warms me inside, in my heart, because I have one. John has a leg, Mrs Hudson has a hip, and I have a heart.

Oh, they are switching to "Auld Lang Syne" now. That song has always been one of my favourites. A very popular old Scottish anthem, based on the ballad Old Long Syne, which was published in 1711 by a man called … Watson.

Should old acquaintance be forgot … la la la …

I still can't hear his voice. What do you have, John? A cold? Well, perhaps somebody tried to strangle him and … no, those times are over, I fear. I wonder what it is like, his new life – working in a hospital, living in a different part of London, having a family, running a charity organisation. Must be boring.

My phone rings. Taking it out of my coat pocket with my ungloved hand, I read the text. It is Mycroft's usual Merry Christmas and a happy new year -text. He has taken to sending a text like this every year since the day of my "death". The news shocked him a little back then, I suppose, until I phoned him to explain how I had faked it. I postponed the call until after the funeral, of course, to make sure even my brother's face looked adequately sad. You never know who is watching, and Mycroft is such a bad actor.

I watched my funeral via webcam and it went well. Just as planned, all the relevant people were there, most of them crying, and nobody seemed to suspect anything. John even came back again a couple of days later, accompanied by Mrs Hudson. They nearly caught me removing the cameras. I had to run to the other side of the graveyard where they could not see me. There I stayed and watched from a safe distance, taking the opportunity to look at them in person one last time.

To me, they seemed rather confused. John apparently argued with Mrs Hudson until she walked away crying, I could not see why. Maybe he had insulted her. He then touched the headstone and made a little speech. A strange behaviour – why would he talk to a stone? For god's sake, even I would not do that.

It was impossible to make out what he was saying, unfortunately. I was worried. Seeing a man jump off a roof and end up lying dead on the pavement can be traumatising. That's what I read in a psychology book – but I had honestly thought that I knew John better. About his likes and dislikes I had collected a huge amount of knowledge during the time we spent together. Buy John beer – good. Poison his coffee – not good. And so on. The list was very long and I'm still keeping it. It is of no use to me anymore and I usually delete useless things, but this one serves as a load-bearing wall in my mind palace. Without it, the whole annexe of the past four years would collapse. The same applies to the list of facts I learned about his past and everything he taught me about makeover shows – well, that is useful. But never had I seen him get worked up over the sight of a dead body. I thought he could handle it. My brother told me later that John also went to his psychologist a couple of times after my alleged suicide, but stopped visiting her shortly after the incident on the graveyard. I assume he regained his sanity quite quickly and it was alright.

In the very end of his soliloquy – or imaginary dialogue – at the grave, the wind carried a few words over to me. Alone was one of them, and another one was miracle.

I perform miracles on a daily basis, John, I thought, but I still can't get the stone to answer you. Although, thinking about it, maybe I could …

Mycroft, however, has turned a little more brotherly since. He even went to Bantleigh School to buy my laboratory equipment back after Mrs Hudson had donated it. In the military lab, you never know what is contaminated with one of the deadly diseases the Americans are doing research on, so I prefer working with my own stuff.

My brother also managed to get my violin back for me, although that resulted in a huge argument with John. Mycroft, who was supposed to take the violin to the United States for me, had to pretend that he wanted to keep it for sentimental reasons. An extremely difficult task for him, I'm sure he was not the least bit convincing. John, who really wanted to keep it for sentimental reasons, pretended that he was planning to auction the violin during the next Baker Street Charity Event. Oh, I would have loved to watch them argue. After nearly two hours of discussion, when Mycroft was about to give up, John suddenly changed his mind. He took the violin and bow and notes from the locker where he had kept them and handed them over. Mycroft could not tell me why, so it was probably about that special ability John has which my brother and I are lacking. We make deductions about people – we look at them and know who they are, what they do and what they're trying to hide by putting little clues together. John is an expert at seeing how people feel. He doesn't have to ask them or rely on previous experience. He just knows how a situation will affect their emotions, sometimes even without looking at them. So did he use this ability of his and see what Mycroft feels? What did he see? Does Mycroft always have feelings? And if yes, does he know? Oh, this is getting confusing.

I would like to play now, but I left the violin in the hotel room I rented for the night. What if I just stood here in the snow with the instrument, took the bow and started to play "Auld Lang Syne" along with their singing? Would they hear it? Would they recognise me? Probably not. The material would be affected by the cold and wet, the strings producing squeaky noises. It would certainly not sound like my usual playing.

Normally, I would reply to my brother's text with a Merry Christmas, brother dear, and even send another one saying, Happy new year, M; S on the first of January. This time I press delete, put the phone back into my pocket and my glove back on. After all the quarrels we've had lately, I do not feel like answering him. He insists on my staying at the army base until further notice. He would have me shot if he knew that I am here tonight. Not to mention the effort it takes to get a flight out of the base without his knowing. To me, enough time has passed since Moriarty's death. The snipers and parts of the consulting criminal's web might have remained, or even been reorganised. In the meantime I have learned enough new ways of dealing with assassins and organised crime to be able to face them. My brother, of course, is convinced that I could not. My return would be difficult, he says, and put too many people's lives in danger, including his and my own. The thought does not scare me in the least. To the contrary: I hate missing the chance to finally be confronted with real people again who could really kill me. In one aspect, he is right, though: It is not easy to come back from the dead. No chance just to show up and say, Hello, here I am, resurrected! The circumstances make it so much more difficult than that.

First of all, I am not sure how people would react. Would they still call themselves my friends afterwards? I played a trick on them which was only partly funny, and that is something they usually dislike and consider as rude. Are three years enough time to minimise the risk of that provoking aggressive behaviour, or does the amount of time between faked death and reappearance even make it worse? Mycroft and I are in this respect certainly not the measure of all things. I have spent a lot of my free time recently looking for examples with ordinary people under similar preconditions, but the data I could dig up was by far not sufficient for a profound statistical analysis. Well, basically, I did it all to save their lives. Does that count?

And then there is the problem of people believing that I was a fraud. I don't care what the hell people think, but Mycroft once pointed out that the discovery of even my death having been a fake would not exactly make things easier for me. Re-establishing my reputation as a detective and police consultant would be next to impossible. The press would hang me upside down on the nearest street lamp, he said. I hope he did not mean that in a literal sense.

I take a step back from the door and look up at the sky. It is cloudy, but a few stars are still shining through. I know nothing about astronomy, but it's such a beautiful sight. One star falls, and I make a wish. And a decision.

This time I won't just sneak away. I will take a risk, right now, when the singing is especially loud. It might be a small risk, but it will at least give me the opportunity to fly back to the States telling myself, it's not that I haven't tried.

I take my glove off again, touch the doorbell button with my thumb, circle it once … twice … then push it in.

Single ring. Maximum pressure just under the half-second. Client!

I wait, feeling a smile appear on my face.

The singing doesn't stop, no footsteps to be heard, nobody comes running to the door. Well, I can't say I haven't tried. I thought it might be loud enough. I would have heard it. And recognised the ringing pattern, of course. I thought he would remember it and know what it means, but then again, it's been three years. Maybe he has forgotten about it already. It was stupid of me to think like that, anyway. I should have known better. I have a chemical defect, and as always, it's found in the losing side.

I wipe my eyes dry with my coat sleeve, turn right and walk away. I put my glove back on. The air is bitterly cold. More snow starts to fall, light flakes getting entangled in my hair. I stand still and look up at the sky again. There are no more stars to be seen. Sleeves and collar of my coat are soon covered by a thin layer of white.

Time to get ready for flying back to the other world. The world of New England, the FBI, the army base and not John. Back to work! I am looking forward to that. A little.

And to the problem of my persistent sadness, there might be a seven per cent solution. Speaking of snow.

The half-frozen crystalline ice scrunches under my shoes as I carry on walking. For films, they use cat litter to simulate this sound. Once I had a case where … no, wait – top secret. Forbidden to talk about. Well, nobody is there to hear it anyway.

Somewhere behind me, a door is opened. Probably by a child stumbling out to see the heavy snowfall. I used to do the same when I was young, armed with my magnifying glass to examine other people's shoeprints. The snow muffles the sound so I cannot tell how far away it is. I should hurry up now.

"Sher… – Sherlock?"

It is a soft and very unsure question. I start to turn around, and a loud and very convinced scream follows.

"Sherlock!"

I look back into the direction of 221b, and there you are, running towards me. Never before have I seen you run so fast, not even when we were being chased down streets or abandoned factory halls, dodging gunfire.

"Bastard!" you shout. "You bloody bastard! What did you think you were doing … "

You push your hands against my chest. My feet slip on the snowy frozen ground and I struggle in vain to keep standing. Falling backwards, I grab your arms and tear you with me. The air is pressed out of my lungs as I land on my back and see stars of a different kind.

"You deserved that, you know", you say roughly. Your lips are twitching, indicating that you are fighting back tears. Crouched on your hands and knees, you stare down at me, obviously waiting for your breathing to slow down. Shifting your weight, you lift your right hand and touch one of the wrinkles between my eyebrows. Yes, that one is new. Does it answer the questions you have? I for one am convinced that I got it from missing you.

Your eyes narrow. Surely you can see that I have gained a little weight from sitting around too much. Not a lot, though, only a few pounds, because the mess hall food always tastes of too much sodium glutamate and I've developed the habit of pacing up and down in my room like a caged Panthera onca when I'm thinking. You have become thin.

"I knew it", you whisper. "I always knew it, but they would never believe me. Are you real?"

I lift my head a little, shake the dizziness off and say, "Yes."

You seem to find it impossible to hug me in this position, so you put your arms around my neck and kiss me. When did you take up wet shaving again, John? I can feel that you cut yourself three times this morning in your chin alone. Besides, you have an inflammation in your lower lip … oh, at least it's no herpes.

"Come on", you command, get on your feet and help me up.

"How did you know?" I ask, curious about what you said before.

"No, I didn't, really", you reply. "It's just … Whenever I met your brother … The expression on his face …"

"He had an expression?"

"It seemed to say, I'm protecting someone. I always wondered who that someone might be." You look up into my eyes, blinking, still holding on to my wrist as if I had threatened to run away.

"He had looked very sad, though, at your … at the funeral, so …"

"Oh, had he? Good."

"… so I thought I was mistaken."

"No, you weren't."

"Obviously." The grip of your hand tightens and for a moment I fear you might hit me again.

"It's … It's a miracle", you stammer. "It's Christmas." Your face lights up and your frown suddenly turns into the brightest smile I have ever seen.

"Let's go back inside, Sherlock. Come back home."

While we are walking back together, you continue talking. "You can have a cup of tea and … sit in your favourite chair, it's still there, we always left it unoccupied for …" You reach into your pocket and take out a handkerchief.

"We can sing another song, and you can play along on Eleanor's violin", you go on. "Once the others have seen … As soon as they are … She's one of Lestrade's kids, you know. Eleanor. Or rather, one of his wife's kids, in case you didn't … know." After using the handkerchief to blow your nose and wipe your eyes, you nearly hand it over to me before deciding for the better and giving me a fresh one.

"How, Sherlock? And why? For god's sake, why? And why have you come back now?"

"Tell me", I interrupt. The most important questions must be answered first. "Is it true that somebody oversalted the biscuits?"

"Yes, right, how did you …" Furrowing your brow, you look completely confused and a little awkward. "Oh, never mind."

"It was you, right?"

"Yes", you admit. "I guess I've been a bit … upset today. Christmas is always the hardest part of the year when you've lost a …"

We arrive at the door. A strange anxiety builds up inside me at the prospect of it being opened for me. You touch the handle, then hesitate, look me up and down and shake your head.

"Honestly, Sherlock", you say. There seems to be a weakness affecting your knees. They are shaking slightly, just like mine.

"Three years. Do you know what I've been …" Your voice fails. "Couldn't you come back earlier, or call or write or just fucking tell me you're alive?Why did you do this to me, you … you …"

It seems that you have run out of insults. Leaning against the doorframe, you shake your head once more.

"John", I begin to explain and lay my hand on your shoulder as I push the door open for us. "My dear John. I am sorry." There is snow on your jumper. You're going to have to change it. It's wet. "I had no idea. It never occurred to me that you would have a heart, too."