Who: Sherlock and John
What: Dealing with the mirrorverse fallout
Where: Sherlock's cabin
When: BACKDATED to just after the breach
Sherlock was in his chair, with the violin. The noises he was drawing from it, could possibly, in some avant garde circles, be called music. Most people however, would agree it was just hideous screeching. The kind that penetrates through walls and irritates with its off-key, off-beat repetitions.