Hero Fiennes Tiffin may boast one of the most famous lineages in British film history, but his recent project with Guy Ritchie proved he has earned his "acting chops" and has kick-started the race to make the surname his own.
Descending on London's South Bank Centre, which had been transformed into the beloved 221B Baker Street, the 28-year-old son of director Martha Fiennes and cinematographer George Tiffin stood front and centre, ready for his close-up.
He played the titular role in Amazon Prime's latest release, Young Sherlock, and was joined by his uncle, fellow actor and star of 1998's Shakespeare in Love, Joseph Fiennes, on set. The 55-year-old took on the role of Hero's father in the reimagining of Sir Arthur Conan Doyle's classic and offered him a helping hand, both on screen and off.
At the premiere attended by HELLO!, Hero told us how he really felt about working with a family member and how it ultimately affected his leading performance, which was quite a step away from his previous lead role as heartthrob Hardin Scott in the After film franchise.
He revealed: "It's a dream. I've always wanted to work with Joe, and anyone in my family in the industry, but it would have to be for the right opportunity. I'm very lucky to have the opportunities that I do to get into this industry, and I felt like before working with them, I definitely wanted to have some time to get some experience and improve my acting chops."
The actor, who previously played a young Tom Riddle in the Harry Potter films, continued: "It was funny, at the start of any job I have a lot of self-doubt, and imposter syndrome.
"You wonder why anyone trusts you to do the job, but you keep that to yourself, you give it your best, and after a while, you get that self-confidence. Then Joe came onto set about four months into shooting and all of that went in the bin and out the window.
At the start of any job, I have a lot of self-doubt and imposter syndrome.
"Matthew Parkhill, our showrunner, said that he saw me shrink to a much younger version of myself, but Joe's so supportive and such an incredible actor. He's also very generous and giving, and I very quickly built up that confidence again and I loved working opposite him."
© WireImageFiennes family values and a budding bromance
The famous Fiennes men, who are also the nephew and brother of Schindler’s List star Ralph Fiennes, were cast by the renowned Snatch director and the series showrunner, who revealed he had some apprehensions before the cameras started rolling.
On the red carpet, Matthew explained to HELLO!: "Obviously, I knew he [Joseph] was Hero's uncle, and I was like, 'How is that going to work?'"
The writer met with the actor for coffee, and conversations during that meeting instantly quelled his anxieties.
"He clearly adores Hero. He just told me all these stories about when Hero was young and how he used to do magic tricks for him. And I said, 'Can I put that in the show?', and so I think it's in episode seven you see that.
"What was so enriching about that was that he had so much love for Hero, and I just thought we could use that in the show and in the story."
Matthew wasn't the only one who drank the family's Kool-Aid. Hero's co-star and the actor who tackled the infamous James Moriarty character, Dónal Finn, gushed over the duo and revealed what it was like to be thrown into the middle of their dynamic.
He shared: "It was brilliant! I feel so lucky that pretty much from the moment I met Hero, every single day we were filming together. I couldn't have asked for someone to be more dedicated, compassionate, and committed to bringing the required energy every single day - and the curiosity and hope to make things even better than what we might have imagined in a rehearsal or when we first read the scenes. That takes a great amount of energy every day so fair play to him!"
I think he is such a forensic, and yet really spontaneous, electric actor.
Moving on to speak about how the actor interacted with his uncle, he noted how "sweet" it was when Joe joined the set and also shared a bonding moment between himself and Hero as both men realised they were "in awe" of The Handmaid's Tale star.
© WireImage
© WireImage
© Getty Images"I think he is such a forensic, and yet really spontaneous, electric actor. I was really glad for some of the lessons that I felt came in through osmosis really and watching him work."
The Sherlock and Moriarty duo were joined by another actor with famous parents, as Max Irons, son of Jeremey Irons and Sinéad Cusack lent his skills to Mycroft Holmes, Hero's onscreen brother.
What is Young Sherlock about?
The Ritchie and Parkhill adaptation of the detective stories sees audiences transported back to the 1870s to a time before Sherlock had become the famous sleuth and Moriarty his mortal enemy.
© Getty ImagesEach of the eight episodes chronicles the development of the teenage boys' friendship, from their initial meeting while at Oxford University together, and takes viewers along for the ride as they chaotically solve a series of mysterious murders.
Young Sherlock premieres on Amazon Prime Video on March 4, 2026.
