After four seasons and a special, BBC’s Sherlock already covered some of the best and most influential Sherlock Holmes books and stories. The modern-day Sherlock series premiered in 2010 and released four seasons consisting of three 90-minute-long episodes, plus a holiday special of the same length. From John and Sherlock’s first case together to the “final problem,” the Sherlock series had a great run and does not need to return. Robert Downey Jr.’s Sherlock Holmes, on the other hand, only got two movies. Therefore, Sherlock Holmes 3 has arguably more potential than Sherlock season 5.

Guy Ritchie’s Sherlock Holmes told an original story, whereas Sherlock Holmes: A Game of Shadows incorporated Professor Moriarty and was loosely based on The Final Problem. Whereas a TV show like BBC’s Sherlock or CBS’s Elementary can cover multiple stories and cases per season, the theatrical Sherlock Holmes movies can only tackle so many storylines at once. There would be dozens of Sherlock books available for Sherlock Holmes 3 to be based on, even if the sequel was not a direct adaptation of any of them. There is a lot of room to expand Downey Jr.’s Sherlock franchise.