Sherlock Soundtrack
This is the gorgeous soundtrack for The Final Problem. If you don't have time to listen to the whole thing right now, at least skip ahead to 29:35 and listen to "Who you really are" - the violin duet that Sherlock and Eurus play together, which leads into the Sherlock music we know so well. It's spectacular!
https://youtu.be/HI5eLUpBkx4