Warning: SPOILERS forWatsonseason 1, episode 7, “Teeth Marks.”
Watsonepisode 7 further develops Moriarty’s plans, but it’s an unseen villain from the books who truly stands out in light of Sherlock’s fate. It’s been known since the beginning thatWatson’scastwould eventually grow to include more characters from the books. And if CBS ever confirmsWatsonseason 2, that roster will likely expand even further. But while Moriarty unexpectedly revealed his face in the first episode, another villain lurks in the shadows who’s only received vague mentions. Episode 7, “Teeth Marks,” elaborates on the danger he poses.

It’s actually important for CBS’Watsonto start including all the Easter eggs that it can.Watson’s critical reviewshave been fair, but ultimately middling. And with CBS losing long-time supporters over recent cancelations such asBlue BloodsandS.W.A.T.,the network’s newer procedurals need to do anything they can to boost ratings. In the case ofWatson, adding an extra layer to the story of Sherlock’s death could be the very hook the series needs. And ifWatson’s most mysterious side villain follows his arc in Sir Arthur Conan Doyle’s books, that won’t be hard to accommodate.
How Watson Teases Sebastian Moran’s Involvement In Sherlock’s Death
Unseen Villains Are The Most Dangerous Kind
So far,Moriarty’s plan inWatsonhas only used hatchet man Sebastian Moran as a bargaining chip. In episode 7, Shinwell receives flowers with threatening pictures attached to remind him thatMoriarty will have those closest to Shinwell killed if he doesn’t play along in swapping Watson’s pills. The episode ends with pharmacist Lloyd taking credit for the pill swap to take pressure off of Shinwell before dying right in front of Shinwell’s eyes. It isn’t stated how Moriarty convinced Lloyd to do this, but it wouldn’t be surprising to learn that he’d received a similar floral arrangement.
I Am Shocked At The Odd Change That CBS' Watson Did To This Classic Sherlock Holmes Character
CBS' Watson includes a reference to a previously unmentioned character from the original Sherlock Holmes stories, but with some changes.
But if Sebastian Moran is this well-known a threat, that raises a troubling question. Aside from ego, why would Moriarty risk encountering Sherlock alone at Reichenbach Falls if there were even a chance he might not survive the confrontation?The most obvious answer is that Moriarty wasn’t truly alone at Reichenbach, and there’s good evidence for this. Moran is known for stealth, so the fact that he isn’t seen in the flashbacks doesn’t mean he wasn’t nearby waiting to pull the trigger in case Sherlock survived. And Doyle’s books establish just such a precedent.

Sebastian Moran’s Book History & How That Fits In Watson’s Story Explained
The Colonel Got Closer To Killing Holmes Than Moriarty Did
Although some adaptations such asBBC’sSherlockignored Sebastian Moranentirely, he played a significant role in Doyle’s stories. Sherlock was originally meant to die for good at Reichenbach Falls, but that changed with the 1905 story “The Adventure of the Empty House.” The story establishes not only that Sherlock faked his death after killing Moriarty, but also thatSebastian Moran was present to witness Sherlock’s survival and attempted to murder him with boulders as he clung to the Falls’ ledge. But that’s not even the least of what makes the tiger-killing Colonel Moran’s inclusion inWatsonso deadly.
Doyle’s Sherlock designated Moran as Holmes’ most dangerous nemesis next to Professor Moriarty.

The same story establishes Moran as one of the reasons Sherlock faked his death in the first place.Sebastian Moran is one of the few villains to commit a murder that Sherlock couldn’t solve, and Holmes faked his death in the hopes it would cause his smarter adversaries to get lazy and slip up. DespiteWatson’s changes to Moriarty, there’s no reason to think this aspect of Moran’s character wouldn’t carry over. He’s a known Moriarty collaborator who Sherlock hasn’t put behind bars. That makes him a formidable foe ifWatsonchooses to feature him in a larger role moving forward.
Will Watson Ever Show Sebastian Moran Now That Sherlock Is Already Dead?
Unfortunately, It Might Depend On The Show’s Ratings
IfWatsonwere to feature Moran at Reichenbach Falls in the same fashion as Doyle’s stories, then there’s one big roadblock.Watsoncreator Craig Sweenyhas already stated thatSherlock is well and truly dead in this version of the story, and Moran’s involvement at Reichenbach in the books revolves very much around Holmes’ survival. Sweeny has indicated he might make an allowance for Sherlock’s return ifWatsonever languishes in terms of ratings or story, but it’s far too early to make that call just yet.
That said, Sebastian doesn’t need to appear at the Falls to pop up on the show. Given his importance to Shinwell’s story and his likely involvement in coercing Lloyd’s death, it would almost seem strange not to feature Sebastian Moran at all beforeWatsoncloses its curtain. Doyle’s Sherlock designated Moran as Holmes’ most dangerous nemesis next to Professor Moriarty. Whether Moriarty survives this season or not, a season renewal could easily justify featuring Moran as an even more actively deadly antagonist.

Watson
Cast
Watson follows Dr. John Watson a year after Sherlock Holmes' demise as he leads a clinic for rare disorders. Despite his return to medical practice, Watson is drawn back into the mysteries and challenges of his past, suggesting that his association with Holmes is far from over.