Craig Sweeny, the creator and executive producer behind CBS's Sherlock Holmes spin-off series 'Watson', has publicly outlined the narrative direction he had envisioned for a third season before the show was unexpectedly cancelled. The medical drama, which saw Dr. Watson resume his medical career six months after the presumed death of Sherlock Holmes, concluded its run after production on its second season wrapped in March.
The series, starring Morris Chestnut as Dr. Watson and Randall Park as James Moriarty, initially debuted in early 2025. Its second season, which premiered in the autumn of 2025, concluded in May with an open-ended finale. This finale saw Watson preparing for surgery for a glioblastoma, a condition that had caused him to experience hallucinations of Sherlock. However, a twist revealed Sherlock to be alive and hospitalised at Watson's own Holmes Clinic in Pittsburgh, prompting Watson to abandon his operation to treat his friend.
In an interview with Deadline, Sweeny elaborated on how these unresolved plot points would have developed. He stated that a third season would have continued to see Watson act as Sherlock's physician, managing ongoing complications from the ailment that afflicted Holmes at the close of season two. Originally, Sweeny explained, Sherlock was intended to exist solely as a delusion in Watson's mind, a device for Watson to learn about his own glioblastoma. However, this plan was revised to allow Robert Carlyle's portrayal of Sherlock Holmes to be present in the real world due to the dynamic it created.
Beyond the central duo, Sweeny indicated that a third season would have brought closure to the storylines of the medical fellows working at the Holmes Clinic. He noted that medical fellowships typically last three years, making the conclusion of Ingrid, Stephens, Adam, and Sasha's fellowships a major thematic focus. The series would also have continued its core focus on unique and compelling medical cases, described by Sweeny as the 'heart' of 'Watson'.
The cancellation of 'Watson' after its second season leaves fans with several unanswered questions regarding the fate of its characters and ongoing medical mysteries. The revelations from Sweeny offer a glimpse into a potential future for the series that will now remain unexplored, highlighting the challenges of television production and the often unpredictable nature of network decisions.