When a secondary school teacher insisted he was more suited to university than drama school, a teenage Nathan Stewart-Jarrett thought to himself, “F**k you! I can go to drama school if I want.” Soon after, he was accepted into the BRIT School and then the Royal Central School of Speech and Drama.

Then, as he was trying to establish himself as a young actor in his early 20s, Stewart-Jarrett was told that he didn’t have a face for television. Within weeks he’d landed the star-making part of Curtis Donovan in the hit E4 series Misfits, the hugely popular sci-fi comedy drama about a group of younger offenders doing community service who obtain superpowers.

But Stewart-Jarrett is done proving people wrong. Now he’s only focused on tackling roles that are meaningful to him. “You still have to prove yourself time and time again,” Stewart-Jarrett tells me over Zoom. “But it’s not just to others, it’s to yourself as well.”

Accordingly, in recent years, the 37-year-old actor has sought characters and films that are more challenging and aligned to his tastes. In the critically acclaimed Femme, Stewart-Jarrett portrays a drag performer who seeks revenge after his life and career are destroyed in a violent homophobic attack. He was a guidance counsellor in the HBO dramedy Generation. While in high-octane action heist series Culprits, which is making its terrestrial debut on ITV on 19 December, his character Joe Petrus leads a triple life as a family man with two children and a husband, a ruthless bodyguard for a mafia boss, and an elite criminal in a high-stakes heist gang.

“A few years ago I made a decision to have more agency in my career. A lot more thought process goes into who I want to play and why. I pick different projects for different reasons, but sometimes I just want to see if I can play a certain character,” he explains.

When he was younger, Stewart-Jarrett never considered being an actor. He initially thought he’d become a lawyer, as he had an unhealthy desire to win every argument he found himself in. His most pressing concern at this time, though, was how much he hated school. “I was on the cusp of being bullied. I was aware it was coming. I was this long, nerdy, skinny streak of p***. I just didn’t fit in.”

It was a conversation with his cousin that changed the trajectory of Stewart-Jarrett’s life. “He went to a school where he could wear his own clothes, play guitar, sing, act, and express himself. That’s where I wanted to go.” The school in question was the BRIT School, a performing and creative arts school which trained the likes of Adele, Amy Winehouse, Kate Nash, and Tom Holland.

“It was life changing for me,” admits Stewart-Jarrett, who attended the BRIT School between the ages of 14 and 18. Suddenly exposed to a mixture of high and low brow culture, he was also encouraged to express himself. “At a school like that you’re helped to examine everything, from Warhol to Shakespeare to Brecht. That energy just permeates and it gives you ideas.”

After getting into the prestigious Central School, he got more serious with his acting pursuits, despite always feeling like he was falling behind his classmates. “It was a very heavy workload. You were there to warm up at 10am [and training] until 6pm. Then afterwards I’d go to work at Hampstead Theatre. It wasn’t a smooth run for me. I feel like I was behind everyone. But I turned up on time. I learned my lines.”

If Stewart-Jarrett felt like he was lagging at Central School, he more than made up for it after getting his degree. Straight out of college he headed to the theatre, with roles in plays including Brixton Stories and a tour of The History Boys with the National Theatre. He also paid his dues in episodes of Casualty, Coming Up, and The Bill, before getting cast in Misfits. “I was really lucky. It was just really quick,” he says. “All of the main cast have said that we didn’t really have time to know what the show was. It’s weird, only now, a few years after the show, are you able to realise how huge it was. There are new, young fans coming up to me all the time to say they watch the show.”

Stewart-Jarrett can’t help but look back fondly on Misfits — but when he was subsequently approached to play other competitive and serious characters like Curtis, he made sure to avoid them, especially since it had become a running joke how different he was in real life. “It was so far away from who I was. It was actually quite a lot of work to play the role.”

After Misfits, Stewart-Jarrett admits to becoming a little careerist, taking roles he didn’t necessarily connect with in the belief they would help increase his profile. “I think there are a number of British actors who have built these big and wonderful careers because they’re a little more careerist,” he muses. “It wasn’t until recently that I was like, ‘Oh no, no, no, no. I need to do this for me and my art. This is about an exploration of artistry. It’s not all about tomorrow. Let’s explore this moment.’”

When it came to Culprits, Stewart-Jarrett was primarily attracted to working with J Blakeson, the show’s creator, co-writer and co-director: “His writing is so specific and just amazing. It was a dream to work with.” Getting cast did prove to be rather stressful for Stewart-Jarrett, though. Not only did his audition involve performing a 16-page scene, but he also had to portray the character at two very different parts of his life. Stewart-Jarrett was also concerned that he didn’t have quite the right physique to do justice to Joe Petrus, who’s nicknamed Muscle, so he came up with a full-proof plan to trick Blakeson and the rest of the casting team. “I wore so many sweatshirts to make me look more muscly. It was a physical challenge. Plus, I’d never stepped into the lead role of a series before.”

But, while Stewart-Jarrett admits to being “terrified” about being up to the task of leading Culprits, he ultimately emanated a confidence and aura that early reviewers have said elevates the show. “Someone said that I marched on set. I didn't do it consciously but I would always be walking with purpose. I think I was very front foot forward. I was owning the space. Owning what I was doing.”

It's a neat metaphor for the approach Stewart-Jarrett is taking to his career in general. “I’ve been acting for quite a while now. As you grow older, you could easily just coast as an actor. But that’s boring.” Watch this space.

Culprits is streaming on ITVX from 19 December 2024.

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