From Benedict Cumberbatch to Henry Cavill, several actors have brought the iconic character of Sherlock Holmes to life on both the big and small screens. Each actor showed an intriguing version of the legendary detective, first created by Arthur Conan Doyle. Now, Guy Ritchie, who directed Robert Downey Jr. in the popular Sherlock Holmes movie and its sequel, is returning with yet another take on the detective.

For the TV series Young Sherlock on Amazon Prime Video, the director is introducing a new cast of actors who will lead the show. 

Hero Fiennes Tiffin as Sherlock Holmes: Fiennes Tiffin, who famously played the role of young Tom Riddle in the film Harry Potter and the Half-Blood Prince, will play a young, 19-year-old, ruthless Holmes in the series. He has previously appeared in several other films, including After, After We Collided, After We Fell, and Picture This.

Zine Tseng as Princess Gulun Shou'an: The Taiwanese actress is well known for her role as Young Ye Wenjie in the Netflix series 3 Body Problem. Her character, Princess Gulun Shou'an, will be shown to be an Oxford University scholar and martial artist.

Joseph Fiennes as Silas Holmes: Fiennes, who is well known for his roles in Shakespeare in Love, Elizabeth, and Running with Scissors, will join his nephew, Fiennes Tiffin, for the series. 

Dónal Finn as James Moriarty: The Irish actor Finn is no stranger to book adaptations. He has previously played Nettly in the Netflix series The Witcher. Finn also briefly appeared in Fantastic Beasts: The Secrets of Dumbledore. In the series Young Sherlock, he will play the role of a criminal mastermind, James Moriarty, who is Sherlock Holmes’ enemy from the book.   

The 8-episode series is based on Andrew Lane's Young Sherlock Holmes book series, which follows the same detective characters Sherlock Holmes. And this is quite a star-studded cast. The entire team was present at the London premiere.  

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During the event, Fiennes Tiffin also opened up about his experience working with his uncle in the series. 

This was a new experience for Young Sherlock actor Hero Fiennes Tiffin, who got his first opportunity to share the screen with his uncle, Joseph Fiennes. He recalled feeling both nervous and confident about their first scene together. During his conversation with Deadline, he spoke about the experience.

“Joseph came in after 3 or 4 months of filming, and as soon as I stepped opposite him, all that confidence went out the window because he’s not just Uncle Joe but Joseph Fiennes, the incredible actor whom I want to impress,” he said.

However, he added that his uncle was supportive and helped him become more confident about his role. The uncle-nephew duo and the rest of the equally talented cast will soon grace the screens on March 4, 2026. 

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Are you ready to watch the cast of Young Sherlock? Let us know in the comments.