Guy Ritchie Returns to Sherlock Holmes With ‘Young Sherlock’ Stars Hero Fiennes Tiffin and Dónal Finn: “He’s Spun It on Its Head”

Hero Fiennes Tiffin and Dónal Finn, the stars of Amazon’s reimagined Young Sherlock series, have been pried away from set to talk to The Hollywood Reporter.

It’s October 2024, and we’ve got a generous 25 minutes to chat while director Guy Ritchie and his crew set up for the next scene at an expansive stately home in the middle of Wales for the Prime Video series. The setting is architecturally rich — the kind of grand immersiveness that makes this origin story of Arthur Conan Doyle’s beloved detective immediately come alive.

In showrunner Matthew Parkhill’s eight-part series (which is now streaming all eight episodes), the After trilogy actor is playing a 19-year-old Sherlock Holmes, not yet the genius investigator we know him to be, who strikes up a close relationship with frenemy James Moriarty during their studies at Oxford University in the 1870s. The all-star ensemble also boasts Zine Tseng as Princess Gulun Shou’an, Joseph Fiennes as uncle to the protagonist Silas Holmes, Max Irons as elder brother Mycroft, Natascha McElhone as Cordelia Holmes, and Colin Firth as Sir Bucephalus Hodge.

Fiennes Tiffin and Finn make an immediate promise at the top of the interview: This is a show with a fresh twist on the widely-told adventures of Sherlock Holmes. Still in costume — waistcoats, pocket watches, the works — they tell THR there’s no rulebook with Ritchie at the helm. After all, this is Hollywood’s Conan Doyle expert (you might recall Ritchie directed both Sherlock Holmes films with Robert Downey Jr. and Jude Law).

“He’s got such a distinctive style that gives you the freedom to push boundaries in every sense,” begins Fiennes Tiffin. “There will be a similar style. You do know what you’re getting with Guy Ritchie,” he adds about the Downey Jr.-Law movies. “But he did those a long time ago. It’s quite hard when you’re in it to really know exactly what the end product is going to look like. But it’s definitely different. Because the nature of the character is different. He is not a detective. He’s at Oxford in the world of students and education and learning.”

Irish talent Finn describes Ritchie as a “walking Wikipedia” on all things Holmes. He says he finds coming in every day “quite exhilarating” thanks to the director’s creative vision. “The thing I’ve loved the most about it is the taking something that seems already explored, and [Ritchie’s] just spun it on its head and invented a new kind of vision for the day in the scene,” he continues. “He’s got an exceptional brain for articulating wit and an appreciation for rhythm and rhyme, and how that unlocks what imagery a character can use. It’s incredible to see it come so naturally and instinctually to someone in the moment.”

THR can attest — watching Ritchie at work on this autumn day is a front row seat to his methodology. He is communicative, succinct and regimented. A man who knows his own mind. Fiennes Tiffin concurs with his co-star’s assessment: “He’s ridiculously intelligent, and quite often, you go into his trailer as he’s workshopping the lines. It’s so entertaining to just sit across from him as his brain passionately wanders and solves issues and adorns and embellishes everything that you’ve already got on the page.”

Both of the young actors are quick to acknowledge their predecessors. Fiennes Tiffin says he, his brother and father have “always bonded over our love for Sherlock,” initially with Ritchie’s films — Downey Jr. “has no license to have such a good [English] accent,” he laughs — and then later, the BBC’s contemporary Sherlock series. “It’s just phenomenal,” he says of the Benedict Cumberbatch-fronted version. “One of my favorite things on TV, and I’ve already watched it twice over before this opportunity came [up].” In fact, such is the strength of the actor’s connection to this interpretation that he had to “refrain from doing any more research, to have some sort of originality. When you bring to life a story that’s been done so many times, it is important to bring a fresh take.”

Finn joins Fiennes Tiffin in raving about Sherlock, but adds that he was drawn to the books when approaching his younger Moriarty. “The great thing about the writing is there’s a correlation between those characters that we’ve seen in different iterations. The similar characteristics are so clear within these characters, it rises to the fore. So you feel like you’re accessing their intelligence and their mental drive, [but] you’re sourcing a character rather than a previous performance of it.”

It helps, of course, that Fiennes Tiffin is playing a version of Sherlock that audiences are less familiar with. “He’s in his youth, he’s a little bit more curious, which is a really interesting way to explore the character, because when we usually meet Sherlock, he’s so knowledgeable and he’s done the rounds already,” he says, teasing some of the antics he and Finn’s Moriarty get caught up in at the prestigious college in England.

It doesn’t mean we’re not to be surprised. Taiwanese actress Tseng, best known for her role in Netflix’s 3 Body Problem, discusses with THR playing an entirely new character as Princess Gulun: “It’s like a blank canvas, which allows me to have the most fun, because I speak English and Mandarin,” she says about the Chinese princess, “and I do fight a little bit. I’m cool.” She jokes about her character’s top-notch chemistry with the teenage Sherlock: “He’s intimidated by me. I think I really like him… I’m not intimidated by him, and I’m okay with the fact that he’s intimidated by me.”

Our extravagant surroundings are no doubt indicative of a lofty budget, with execs hopeful that Young Sherlock will prove as revitalizing for audiences as it has for the cast and crew. The show’s lead is certainly banking on the uniqueness of seeing Holmes a couple of years before he hits peak prodigy, as well as the allure of witnessing him and Moriarty, well, get on: “They quickly bond,” says Fiennes Tiffin. “You don’t even need to read the pages to know that it’s going to be an exciting dynamic, especially when you know that, ultimately, they’re not going to be best friends forever.”

All eight episodes of Young Sherlock are now streaming on Prime Video.