What’s Next for ‘Watson’ After [Spoiler]’s Surprise Casting as Moriarty?

The series premiere of CBS’ Watson featured a shocking casting for the role of antagonist James Moriarty — but how will the twist continue to play out?

Warning: Spoilers below for the series premiere of Watson

During a sneak peek of the series, which aired on Sunday, January 26, John Watson’s (Morris Chestnut) acquaintance Shinwell Johnson (Ritchie Coster) had a secret meeting with the infamous Moriarty, who was responsible for Sherlock Holmes’ death. The role was revealed to be played by Randall Park, with Chestnut praising his costar’s performance ahead of the premiere.

“First of all, Randall Park — aside from being an incredible actor — he’s a great person. He did a great job on the show,” the 56-year-old actor exclusively told Us Weekly. “He quite possibly will reappear multiple times throughout the entire first season.”

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Chestnut teased that Moriarty will be “definitely looming” over Watson, adding, “He’s definitely had his effect on all of us — not just Watson. He’s definitely affected all of us. Throughout the course of the season, I would say the pilot is probably not the last you’ll see of Moriarty.”

Based on Sir Arthur Conan Doyle‘s Sherlock Holmes stories, Watson takes place six months after Moriarty kills the legendary detective. Watson must come to terms with the loss of his best friend and partner by resuming his medical career as the head of a clinic dedicated to treating rare disorders.

“I did not consult any other [past] Watson [performances]. I did, of course, read some of the books and I looked at some of the other projects out there. For me, I felt that this character was different because the other Watsons are primarily not the focus,” Chestnut explained to Us of his preparation. “The story is always told from Sherlock’s perspective, so this story is being told from Watson’s perspective in a very specific way. We’re part of the mythology, but the clinic and being a detective is not part of the mythology.”

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While Watson mentions Sherlock Holmes numerous times, the character has only been seen from behind. According to Chestnut, it remains unclear whether the show will cast someone to play Holmes. “I wish I knew if we were ever going to see Holmes in any type of capacity,” he told Us.

Chestnut’s character will share the screen with numerous other newcomers. Eve Harlow plays a highly skilled neurologist named Ingrid with a questionable past, while Peter Mark Kendall plays twin brothers — Stephens and Adam — who are infectious disease and functional medicine specialists. The show also features Inga Schlingmann in the role of Sasha, a specialist in rheumatology and immunology. Rochelle Aytes rounds out the cast as Watson’s ex-wife, Mary.

“Watson is not going to fully be able to do everything by himself. He needs his team,” Chestnut noted. “There are going to be moments throughout the season where certain things may have created some space between and his team and there may be some things that happen to draw them all closer together under a common cause.”

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Viewers shouldn’t trust everyone, though — especially with Moriarty still at large.

“We cannot trust everyone on the team. But I would definitely say all of these doctors are very special in their own way. They’re very special and extremely smart doctors. Watson has assembled them because he can no longer just look at a person and just not see anything,” he explained. “There are a number of things that Watson sees when he has interviewed all of them that intrigued him a little bit. They are mysterious and … we don’t know everything about them because they’re secretive. But there’s something in them that’s really piqued Watson’s curiosity.”

Watson returns to CBS Sunday, February 16, and new episodes stream the next day on Paramount+.