Okay. I have had this Headcannon of John playing piano with Sherlock on violin for a long while and a picture on Tumblr inspired me to put it into words so…here? Enjoy!~ (Mary isn't here- but not because I don't like her. Just because that is how this worked out)

You and I by BrunuhVille is the song I picture John playing if you're curious. (The song River of Tears (No Voice) by the same person KILLS ME)

Sherlock plays: A Time for Us from Romeo and Juliet
They play Time Forgotten by Brian Crain together

O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~O~

When Sherlock finds out, he's actually completely and utterly floored.

There was no sign that he noticed, no slip of the tongue that would tell him, no hint that John knew how.

So when he walks into the old Church by the graveyard where the newest murder had taken place he is surprised to see John standing there with one hand hovering over the top of the piano before drifting down to ghost over the keys.

Something about the look on John's face, a look Sherlock doesn't understand, stops him from making the demand that John 'Come along' as he had planned and instead he approaches John silently and quietly.

"Were you at your funeral?"

Sherlock turns to look at John's face and there's something there, but he can't see it and John never really talks about anything relating to 'The Fall' so this is very odd for Sherlock, but he answers John. "No."

He is always honest about anything pertaining to 'The Fall' when John asks, especially after his reaction to being lied to and Sherlock's own desire- no matter how he tried to deny and hide it- to be honest with John, to bring John into his plans and such because for the entire time he was 'dead' he had thought that he may not get the chance to have John running beside him again, and then when he had come home and John had been so angry with him, had walked away and Sherlock was sure he wouldn't get to run with John ever again except this was worse because at least before on the run he had thought he would be dead if he never saw John again, but seeing John and John not wanting to have anything to do with him…well Sherlock really didn't like it so he had promised himself to never create a situation where that scenario had any probability of happening ever again. And that meant honesty.

"It was too dangerous. I made a point of visiting when you were alone at my grave, but only then so there was no chance of anyone seeing me."

John turned to look at Sherlock, his hands gliding absently over the keys on the grand piano, his eyes dark with remembered pain and whispers. "I played for you, you know."

And Sherlock blinks as it registers what John is saying and he opens his mouth to start deducing this new information and how John managed to hide it from him, but the look on John's face, the way he held himself, the way he touched the piano as if he were touching a cherished friend, made Sherlock pause and instead he asked "What did you play?"

And John looks up at Sherlock and he asks "Would you like to hear?"

And Sherlock knows, he knows, that this is something special, that John is offering him a gift though he isn't quite sure how. "Yes."

John slides behind the piano and his hands glide over the keys in an elegant sweep as he runs a few scales just to get his hands ready and to check the tuning on the piano. When John is ready and begins to play Sherlock finds his eyes widening in surprise.

He has no idea why John didn't play more often.

John loses himself in the music, everything about him transforming as he lets the music sweep him up and pours his emotions into what he is playing.

Sherlock finds that he is holding his breath as he thinks "John played this for me? This is how he felt?"

Because the piece that John had played for Sherlock's death is haunting and melancholy. It is a song of mourning a song of 'could have been' and 'what if' a song of farewell and love and loss. A song of wondering what happens next, because how does the world spin on when the sun had no right to rise into the sky ever again, a song that conveys being so very lost and confused and so many other things and Sherlock is floored because….

…this?

This was how John translated his death on a piano?

He finds his fingers twitching for his violin, because Sherlock has the desire to respond to this.

He wants to show John his side of the story.

He wants to show John that Sherlock had been just as lost and confused. That he hadn't even known how he was going to get used to there being no one there to watch over him and 'shoot the cabbie' when it was needed, that he had no idea how lonely he would be now that he had gotten used to someone understanding him. Sherlock wants John to know that he had missed him and all the little things that he had adjusted to and loved without even realizing it until it wasn't there…He wants John to know that he had not been alone in suffering.

Sherlock had always been bad with words…but he could do this. He could play for John. He could share his side of the story.

When the music ends, Sherlock doesn't cry. He opens his eyes and stared down at John in silence, his eyes conveying a million different things he could never actually say, and John is staring at him and understanding 1000 things, but Sherlock needs him to know so he asks John "Come home?" and the two men head back to Bakers Street where Sherlock makes a beeline straight for his beloved violin and turns to John telling him "Listen."

And he plays.

He plays a song of loneliness and wondering. A song about being lost in the dark and staggering forward one step at a time because you live in hope that the light is there at the end of that tunnel. A song that tells John he had been missed, that Sherlock had wished he was there, but had been determined to protect him by leaving him alone. A song that conveys hope to see each other again at the end. A song for forgiveness.

And John listens and he knows.

He closes his eyes and he listens and hears all the unspoken things, all the things hidden in the music and he nods once.

He has heard him.

O~O~O~O~O~O~O~

Months later, Sherlock and John are back to running the streets together and solving the unsolvable.

Nothing has really changed at the core. They are still John and Sherlock. Sherlock still annoys everyone, still has to be pestered into taking care of his body, still runs off without John and still calls everyone an idiot. John still comes in behind Sherlock to get the information Sherlock has offended someone into keeping, he still pesters Sherlock into eating, still runs after Sherlock even if he's a little late, and still thinks Sherlock is brilliant.

There is only one key difference.

Now the two men will play together sometimes when all other methods of communication fail. It is rare and beautiful, but the two men can create beautiful music together. They can share hundreds of unspoken words in the music.

The two men will go find themselves a piano and Sherlock will bring his violin.

The first time the two play together it is on a street corner. It's around 3 in the morning and no one is outside except for the two of them- having just chased down a murderer- and John sees the piano on the corner of Bakers Street. He stares at it and Sherlock slips away just long enough to retrieve his violin.

The first piece they play together is slow. It's a song about discovery. A song that conveys a slow building happiness and wonder. A song that brings about the images of winter becoming spring and the feeling of new hope.

There in the early morning the two men create a beautiful piece of music with no one but Mycroft- who sees the entire thing through the CCTV- is aware of.

When all is silent both men open their eyes to look at each other and smile.

Everything is alright.