Sebastian Moran is an assassin who worked for Moriarty.
Sebastian Moran is an ex-Royal Marine turned assassin for hire. He served a prison sentence of six months at Brixton Prison for beating up a Manchester United fan in 2011. He is hired by a man named Moriarty to kill seemingly random people. He receives these names on coded messages via text messages. He has killed at least 37 people on orders by Moriarty. He kills these victims by hanging them upside down on a tripod, then draining them of blood, and finally dumps their bodies in the ocean.
Moran is also a huge fan of Arsenal (an English football team) as he watches their games before, after and during his assassinations, and while in prison he watches part of an Arsenal game and sings their theme song before attempting suicide.
|Moran first starts killing for Moriarty in New York City after Sherlock Holmes moved there. He leaves a cutout-letter note in Sherlock's home under the alias of M, not knowing Sherlock has security cameras in his house, and now knows his face. Sherlock then sets out to find him to torture and murder him. Sherlock captures Moran just as he is about to make his next kill. Sherlock believes Moran killed his ex-girlfriend Irene Adler (since the scene of her faked death had the same M.O.) and brings him to one of his father's properties to interrogate him. Moran resists Sherlock's intimidation and beatings, and willingly reveals he didn't kill Irene, as he was in prison at the time of her murder. Moran suspects his employer, Moriarty, was the one who killed Irene Adler. Moran realizes he has been set up by Moriarty and vows to cooperate with Sherlock as revenge. Sherlock brings him to the 11th Precinct and Moran denies that Sherlock kidnapped him. ("M.")
|Moran, now in prison, informs Sherlock of a murder ordered by Moriarty, staged to look like a heart attack. Sherlock later returns to have Sebastian solve a coded message from Moriarty. Moran lies and tells Sherlock that he doesn't understand the message. Sherlock later solves the code, and it is revealed that the message was a threat to Moran telling him to kill himself, or his sister would die. Moran is then seen committing suicide by slamming his head repeatedly into the wall of his prison cell. Whether he survived is unknown. ("A Landmark Story")
- Arthur Conan Doyle's Sebastian Moran on Wikipedia, which Elementary's Sebastian Moran is based on.