From: ep. 3.1
Character name: Sebastian Moran
Reference: In the original canon, Sebastian Moran is a colonel, not a peer of the realm, but he shares the distinction in this episode (very nearly named after the original story: “Empty House” = “Empty Hearse”) of being the central villain of the first story after Holmes’ return from his supposedly fatal end at the Reichenbach Fall.
Moran is one of several suspected terrorists Sherlock calls his “rats,” so when we find a bomb set up in a tunnel called Sumatra, we also of course hear the echo of a never-penned, only-mentioned adventure called the “Giant Rat of Sumatra.”