Set after the Fall. A supposedly dead Sherlock returns to his John, not realizing the deadly consequences.
Forgive any mistakes. I took a basic idea that I'd written out and ran with it. Not edited, not brit-picked, just my brain vomiting creativity all over my keyboard.
The gun is in his hands before he realizes it. The trigger is pulled and there is an odd, acrid smell in the air. John knows that even Sherlock's famous reflexes aren't fast enough to dodge a bullet.
He wants to blame Sherlock. He wants to scream. He even wants to cry. What he does instead is reach for his phone and text Mycroft.
I know you're watching. Help.
An answering text appears within seconds.
I am on my way.
John paces while he waits for Mycroft to come make it better. He wonders why Sherlock is sneaking up on him in the dark, when he should be dead.
He doesn't bother to hide the body. He hopes Mrs. Hudson heard the report and will come investigate. She is too used to gunshots in 221B to call the police for every little shot or bizarre sound. He hopes Mycroft hurries.
Finally Mycroft lets himself in. He takes in the body on the floor and the gun in John's hand. Without a word, he helps John maneuver the body down the stairs, where Mrs. Hudson is blessedly sleeping, and into his usual black car. A team is waiting for them and for a sick moment, John is afraid that Mycroft will help him vanish. Permanently. No one will find his body if Mycroft doesn't wish it.
Instead, after a tense ride, the team silently buries Sherlock in the previously empty grave and disappears. Mycroft guides John to a warehouse and explains what Sherlock was unable to. John nods silently and leaves. Mycroft does not stop him.
Three months later, one Mrs. Turner calls the police to 221B Baker Street. The official story is that an intruder broke in, stole John's gun, and shot Mrs. Hudson and her tenant. If there are no unknown prints, no witnesses who saw this man but heard his shots, and the bullets match the one found in the "unsolved" Jefferson Hope file, Lestrade isn't talking.
Wow. Much darker than I imagined it would be at first. R&R pl0x!