How Does ‘Watson’ End? Series Finale Returns to Baker Street

CBS’ clever medical drama comes to an end on Sunday, May 3. The Watson series finale sees the titular doctor (Morris Chestnut) face his brain tumor while dealing with the return of his friend, sleuth Sherlock Holmes (Robert Carlyle), a murder outside the hospital (hello, Sebastian Moran!), and a revelation from Mary (Rochelle Aytes). Warning: Spoilers for the Watson series finale ahead!

In the beginning, Watson is, albeit a bit reluctantly, willing to have the surgery for his brain tumor. But when he gets word that Sherlock, whom he’d been hallucinating all season, is actually alive, he hurries back to UHOP to get to the bottom of what’s ailing him, all while everyone is just trying to get him to take care of himself.

So, how does Watson end? Does John live or die? Is everything wrapped up in a bow, or did the canceled show leave some loose threads? Read on for everything that happened in the series finale.

Does John Watson die of a brain tumor?

With his doctor warning him that his tumor will cause pain, memory loss, and seizures, and if he wants to come out of this still himself, he needs to have the surgery ASAP, Watson agrees … until he learns about Sherlock’s return. Then, he leaves, with an “I’m sorry” written under Care Team Communications on the board in his room for Mary.

His fellows aren’t happy with him for not focusing on his own care, and once Sherlock, after regaining his memories, learns how bad his friend is, he, too, gets on his case. Watson’s doctor, meanwhile, is willing to come to Pittsburgh to do the surgery. But Watson insists on caring for Sherlock first, even as the sleuth argues that he’s already taken him a long way and he should be looking after himself. It gets even more complicated when Moran enters the picture and insists he fix Sherlock to make him useful again first — with a threat hanging over Mary’s head.

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But then Watson has a seizure that lands him in a hospital bed at UHOP. His brain’s firing like it’s stuck in a loop, Ingrid (Eve Harlow) explains, pushing him to care for himself. The worst-case scenario is that he has a seizure that doesn’t stop, which is often fatal. And if it’s not, he’ll lose language, memory, and everything that makes him him. “Dr. Watson, John. You mean something to me,” Ingrid says, emotionally. “You gave me a place in this awful, beautiful world. And if I have to visit you in a long-term care facility every day forever, I’ll do it. But please, please, don’t make me.”

But Watson does keep pushing to figure out what’s wrong with Sherlock, to the point that he does have that seizure that won’t stop, forcing him to be put on a ventilator. He’s also put on medications that mimic a coma, but even if the seizure stops, they won’t know what’s left.

One by one, everyone visits the unconscious Watson. Shinwell (Ritchie Coster) wishes him luck. Adam (Peter Mark Kendall) tells him he loves him, a follow-up to an earlier exchange, while his twin Stephens thanks him for everything. Sasha (Inga Schlingmann) promises they’ll all be waiting for him. Ingrid walks away without saying anything. And Mary tells him that her entire world changed the day she met him, and she’s always there with him. That’s when Watson wakes.

“Do you remember?” he asks, and she turns back. “That day in your conference room, you were kissing Josh, and I walked in on that. You remember? I was there to say I love you. I have this picture of you and me, and we’re living on Baker Street in London, we’re having breakfast, but we’re not talking because we don’t need to talk. We have everything we need.” Mary loves that picture. She tells him he’s going to be OK because she can’t imagine a world without him. And she kisses him before he goes in for surgery.

After that, we see the Watson title card, but the episode doesn’t end there. Rather, it then ends on Baker Street, with Watson at 221B. Watson lives!

Is Sherlock Holmes alive?

“There were two men, Holmes and Watson, Watson and Holmes, and they did the most extraordinary things,” Sherlock says in his hospital bed, before he remembers who he is. He’s in bad shape, but he does somewhat quickly get his memories back. “Good morning, Watson,” he greets his old friend. “I understand I’m quite unwell.” He can’t remember much but knows he wanted to fake his own death and went into the Falls after Watson.

The team cycles through a few diagnoses, Sherlock’s heart stops, and Watson has his seizures before they’re able to figure out what’s wrong with the sleuth. As Sherlock had wondered, both absorbed whatever radiation was lingering during the Cobalt Fissure case, so why didn’t they get sick together? Watson figures out they did — his brain tumor, and as he diagnoses before his seizure that won’t stop, Sherlock’s genes are being altered. Now that he’s being treated, he’s going to be fine. They’re alike, even in illness, Holmes and Watson.

Colin Bentley/CBS

Does Shinwell kill Sebastian Moran?

Eddie Izzard guest stars as Sebastian Moran, who shoots, at random, a nurse entering the hospital. After Moran approaches Watson about Sherlock, the doctor turns to Shinwell, who, of course, has a history with Moriarty’s former cohort. Shinwell’s changed, but he can’t forget that Moran killed those who took care of him … maybe? Instead of passing along the information to Lestrade (Rachel Hayward), Shinwell tracks down Moran, who suggests that the couple isn’t dead and offers up two others, including the person watching Mary. Will Shinwell beat up Moran or let the police handle it and return to the life he was living without violence?

The answer is sort of both. Shinwell returns to his fiancée Carla (Margot Bingham) — maybe not anymore? — with bloody hands, having knocked out four of Moran’s teeth until he got the location of those who looked after him and are apparently alive, then called Lestrade. He can’t lose this, he tells her. If there’s still a home here for him, he has to come back. Carla doesn’t give him an answer.

Do Watson and Mary end up together?

Yes! After we see Watson on Baker Street, it’s Mary who opens the door to 221B and remarks that he’s home early. He follows her inside.

Where does the Watson finale leave the fellows?

In the aftermath of learning that it was Beck (Noah Mills) pretending to be her birth mother, Sasha isn’t smiling anymore, Ingrid notes. She does track down her real mother, offering Sasha the file if she wants to take a chance.

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Meanwhile, Adam’s a new father to triplets and thinking about his own father. He asks Stephens about their dad’s potential suicide and makes his twin promise that if that’s ever him, he’ll call him because he can’t lose him. But Stephens isn’t worried about that, not anymore, because he can see a future.

But that future is going to look a bit different than he thought. When he tells Sasha he wants to try to have kids and even starts talking about a wedding, in the aftermath of Beck, she’s questioning everything. She thinks she’s been a fool for being optimistic, and so she plans to change some things. If she doesn’t know who she is, how can she know who she wants to be with? With that, she walks away from Stephens.

Ingrid continues to face questions from Lestrade about what really happened to Beck — and her father. (As she tells Sasha, the detective says she’s “a bad person to be a bad person around.”) Ingrid says it was self-defense, but Lestrade reveals Beck had hidden cameras in his condo that caught her not leaving once she had his laptop. Ingrid sticks to her story, but Lestrade’s not letting it go. Just because he hurt her friend doesn’t mean she’ll get a pass. Ingrid walks away and returns to group therapy, introducing herself with, “I’m Ingrid Derian, and I have antisocial personality disorder.”

What did you think of the Watson series finale? Let us know in the comments section below.

Watson, Streaming Now, Paramount+