sketchlock:

shaddicted:

mid0nz:

This is Sebastian Moran. The only thing missing from Moriarty’s “Sherlock” scratchings is the “Get” part.

Gatiss was asked at one point if he could give us any hints on how Sebastian Moran will be portrayed since he hasn’t been in the series yet, to which he replied with his evil little smirk, “Hasn’t he?” – groovyhedgehog (x)

And

Someone asked about Sebastian Moran and how they intended to bring him into the series. Mark carefully quoted nothing but canon about his perception of the character, then continued, “I can’t say any more or it would spoil the surprise.” “Or the lack of it,” added Steven pointedly. –arianedevere (x)

It’s a lack of surprise because Moran’s already been introduced. Mycroft lets Moriarty and Moran think he doesn’t know that Moran’s “infiltrated” Mycroft’s operation. With Seb at his side, Mycroft can keep a close eye on him. (The added benefit is that Mycroft can watch Moran beat the crap out of Moriarty!) Mycroft can also feed Moriarty false information through Seb as long as Moriarty thinks he’s fooled Mycroft. It makes much more sense than the theory that the sniper at Bart’s is Moran. Moran’s not a mere sharp-shooting soldier. He’s Moriarty’s second in command- a high ranking military officer with an honorable record. Who better to employ him than Mycroft?

ACD says:

[Morarty’s] chief of staff is Colonel Sebastian Moran, as aloof and guarded and inaccessible to the law as himself.” 

Mycroft shows John the sniper’s photo early in TRF along with all the assassins that Sherlock tells John are after the key code. The beauty of Mycroft’s duplicity is that if either the sniper or this guy surrounded by all the creepy “Sherlocks” is Moran, Mycroft knows him & what all his movements are. 

Mycroft is smarter even than Sherlock, remember. (“It was the Li-Lo, Sherlock.”) He’s got this one under control.

Okay, this is very, very clever.