Author's notes: this story has been torturing me for THREE days. I just NEEDED to write it in order to get better. Sorry. And I also wish to thank my wonderful beta-reader, PrincessNala.
Warning: major characters deaths.
The day it happens is the day when Sherlock's life falls apart.
His first clue is John not appearing for breakfast. Sherlock hates waiting, so he barges into his flatmate's room and stops abruptly, instantly realising that something is terribly wrong. John is too still in his bed, and when Sherlock carefully edges closer, tentatively laying his hand on John's forehead, he is shocked at how cold the doctor's body feels. He snatches his hand back and stands motionless, his mind processing everything that he feels and sees infuriatingly slowly. Finally he fishes out his phone and dials Mycroft's number.
Sherlock vaguely remembers the next few days. He consciously shuts down every emotion that surfaces, and completely detaches himself from the rest of the world. All that he feels is emptiness, slowly eating him away from the inside.
When the cause of John's death – brain aneurism – is announced, Holmes reacts with a short dry laugh. His mind helpfully supplies him with the details of their first case together – "A study in pink", as his faithful blogger named it. It's ironic, really, that John died from the same thing.
Mycroft takes care of all formalities, and per Sherlock's request, John Watson is buried in the Holmes family crypt. The engraving on the stone slab reads:
John H. Watson
Friend and soulmate
Just like that, no date, nothing else.
The memorial service is held near the crypt. A few people present, and Sherlock is amongst them, but he stands slightly apart from the group, beneath the tree, dressed in his favorite coat, scarf woven tightly around his neck, gloved hands thrust into his pockets. His head is bowed, and a light breeze plays with his black curls. Only when the others leave, he goes slowly inside the crypt and traces the engraved words gently with his fingertips, then rests his forehead against the cool stone.
"Why?" he whispers brokenly. "Why have you done this to me? Why did you leave me, John?"
Tears flow freely down his face, but he never notices; painful sobs wrenched from his chest, and suddenly he can't take it anymore. He crumples to the floor, a keening wail starting at the back of his throat…
When he finally leaves the cemetery, Mycroft is waiting for him in the familiar black car. Sherlock silently gets inside, and vehicle takes off in the direction of Baker Street.
Since that moment, Sherlock has practically locked himself inside his flat. He spends all his time simply laying on the sofa in the living room and staring at the ceiling. Concerned for his wellbeing, Martha Hudson attempts to spoon-feed him, and, to her amazement, easily succeeds.
A week later, anger comes. One night Mrs. Hudson is woken by Sherlock screaming and, judging by the sounds, singlehandedly destroying everything in John's former room. Only when shouts and crashing sounds stop, the landlady dares to go upstairs.
She finds Sherlock in the completely demolished room. He sits in the middle of the debris, catatonic, his hands clutching John's beige woolen jumper tightly.
Terrified and not sure what to do, she calls Mycroft. The elder Holmes arrives shortly, accesses the whole situation and whisks his little brother away into some private clinic. There the great Sherlock Holmes constantly watched over, IV-fed and visited every day by his older brother. Mycroft spends an hour sitting in the chair near Sherlock's bed and trying to talk some sense into his sibling. He finishes his speech usually with the catchphrase: "Think it over, brother dear".
Evidently, Mycroft's words sink in bit by bit, because one morning Sherlock unexpectedly snaps out of his plant-like state. Gradually he becomes more active, starts to walk and talk, but still he is no more than a bleak shadow of his former genius.
Everything changes during one of Mycroft's customary visits, when Sherlock hesitantly asks his permission to return to Baker Street. The elder Holmes studies his hopeful brother and carefully agrees, on a condition that there will be constant surveillance over the flat. Sherlock shrugs his shoulders absentmindedly and nods.
The first thing Sherlock does when he gets back to his flat is complete reconstruction of John's ruined room; he and Mrs. Hudson working side by side, methodically restoring everything as it was. Sherlock even asks his brother for some surveillance photos of him and John together, frames them and puts in various places around the room.
After that, life in Baker Street 221B almost returns to normal. The world's only consulting detective again starts to take on cases, and Detective Inspector Lestrade is always happy to assist him with that. But there are moments at the crime scene when Sherlock suddenly looks back over his shoulder, as if expecting to see his friend beside him, and when Lestrade once dares to look close enough, the amount of pain and despair reflected in younger man eyes forces the Detective Inspector to literally stagger back. And Sherlock is obviously not the same: he walks slowly, occasionally limping slightly, his voice too calm and controlled, and his face unnervingly impassive.
The manner in which he spends his time at home changes too. Despite his usual fondness of various electronic devices he starts to write some mysterious research, using pen and paper. He even buys a strongbox and locks all materials inside when he is out.
He eats, sleeps and functions like normal human being. But sometimes in the night his violin cries, mourning the life he'll never have.
Sherlock's life ends on one sunny spring morning. Mrs. Hudson finds him dead in John's bed. The younger man's face calm and serene, a smile playing on his lips, and he clutches to his chest a framed photo of him and John – his favorite, where they are smiling at each other. Strewn across the floor near the bed are the papers of Sherlock's last research on brain aneurisms. Unsurprisingly, that is the exact cause of Sherlock's death…
Mycroft Holmes buries his younger brother alongside his loyal friend, John Watson. There are two lines on the cover stone:
Sherlock Holmes
A brilliant mind which willed himself to die
Beneath engravings on both stones – a finalising one:
April 21, a year apart.