this fic gave me hell, seriously. i didn't even get anyone together! madness.
Sherlock and John aren't the first Holmes and Watson to inhabit 221b. Two men in the late 19th century would've gone down in history as the greatest crime-solving duo to walk the face of the Earth. Instead, all traces of them have been obliterated. Something, somewhere, went horribly wrong.
It's up to Sherlock and John to figure it out before it happens again and the clock is ticking.
ETA: Now edited, thanks to
( The Adventure of the Empty Room )