That was the single:
Best episode of Sherlock ever!!
Everything about that episode was just brilliant and I have to say that the writing was far superior to that of Doctor Who. Benedict played such a fantastic part once again as Sherlock and most of the episode I wanted to cry for him but honestly that was the best piece of British TV I've ever watched.
Look in a dictionary and you will find this picture by the definition of a perfect couple:
♥