Kirk Jones was feeling nervous. The director was two weeks away from shooting his new film, a biopic of the pioneering Scottish Tourette syndrome campaigner John Davidson, and he still hadn’t seen his lead actor perform any of the script. Jones had been impressed by Robert Aramayo in the supernatural Netflix series Behind Her Eyes, and liked the actor when they met over Zoom.

He then invited him to Galashiels, to meet Davidson in his home town, where he was convinced Aramayo was the right choice for the role. “I was confident enough not to feel the need to meet 50 other actors and audition them,” he says. But “I didn’t ask him to read”, he admits. “Looking back, I think that was insane.”

His gamble paid off. When I Swear premiered at the Toronto International film festival in September, Variety deemed Aramayo “flawless”, IndieWire praised his “striking, star-making performance” and Screen International marked the actor out as “a major big-screen talent”. Aramayo is best known for playing Elrond in The Rings of Power, Amazon’s megabudget TV prequel to The Lord of the Rings, although Game of Thrones fans will remember him as the young Ned Stark. But his latest film feels like a throwback to a certain kind of British movie; like The Full Monty or Billy Elliot. I Swear is a social issue film, a tearjerker and a feelgood comedy, too. It’s a peach of a role for Aramayo, who portrays Davidson’s various tics with technical nuance and sensitivity, and importantly, nails the campaigner’s charisma.

A week before the film’s premiere, I meet Aramayo in the basement of the Curzon Soho cinema in London. The 32-year-old is unassuming in a beige Patagonia hoodie and jeans, square-jawed but still boyish, and clean shaven with a mop of curly hair. He greets me warmly, orders a cappuccino and launches into a self-deprecating story about how he’s spent the morning making “a terrible audition tape”. A “proud Yorkshireman” and “massive Leeds United fan”, Aramayo has lived in New York since moving there to study at 18, but retains his East Yorkshire drawl.

Walking the walk … Aramayo with Francesco Piacentini-Smith in I Swear. Photograph: Graeme Hunter/Studiocanal

In the opening scene of I Swear, the adult John Davidson is awarded an MBE, and on receiving it, accidentally shouts “Fuck the Queen!” Tourette syndrome is a neurological condition that induces physical and vocal tics such as twitching, shouting and spitting. According to Tourettes Action, there are more than 300,000 people living with the condition in the UK. Aramayo says meeting Davidson was the first time he’d encountered someone living with Tourette’s, though he’s quick to suggest he may have met others without realising it.

Davidson first developed Tourette’s at the age of 14. When he was a teenager, he was the subject of the BBC documentary John’s Not Mad. First broadcast in 1989, it is a time capsule of relative ignorance about the condition. I Swear dramatises his attempts to pursue a normal life in spite of that ignorance, one involving employment, dancing and girls.

I talked to John about anything and everything. Not to impersonate him, to find his energy

“People used to call John Davidson ‘Fuck off John’,” says Aramayo. Before making the film, he says, “like anybody else who hasn’t yet had the education, I would have thought it was all about swearing.” But coprolalia, or involuntary swearing, only affects around one in 10 people with Tourette’s, he says: “It is far more complex than that.” In the film, we see Davidson also juggling intrusive thoughts and OCD.

Aramayo, who does not have Tourette syndrome, started to do more research. He read Evie Meg’s memoir My Nonidentical Twin and was struck by how the author “laughs with” her condition and “has fun with it”, he says. “It’s part of who she is.” He also spent time with Davidson in Galashiels, renting a house nearby “for about a month, maybe more”. He accompanied Davidson to the local community centre, where he has a job as a caretaker, to understand the pride he takes in his work. They went on dog walks, watched football and attended choir concerts together. “I just tried to get him talking about everything and anything,” Aramayo says. “I didn’t want to impersonate him, but I wanted to find his energy.”

Now we’re Tolkien … Aramayo in The Lord of the Rings: The Rings of Power. Photograph: Landmark Media/Alamy

A big part of that energy is Davidson’s mischievous streak. Aramayo’s performance is a dramatic one, but the scenarios in the film are often funny. At a job interview, his future employer asks him to make a cup of tea. “I use spunk for milk,” he accidentally blurts out. As a comedic set-piece, it’s irresistible, but Aramayo doesn’t play the moment for laughs. “A lot of the situations you see in the film are things that John himself laughs at,” he says. “I’ve been told those stories, and I know how he feels about them.” The film’s tone, he says, was something he and writer-director Jones discussed daily.

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“I wasn’t nervous about showing the level of humour that comes from a condition where you have no control over what comes out of your mouth,” Jones explains over Zoom. But, he says, “it’s not Carry On Tourette’s”.

Before the film had been greenlit, Jones was considering casting an actor with Tourette’s. He tested a few scenes with Davidson, but the result was “nothing short of a disaster”. He felt uncomfortable asking Davidson to suppress his tics, and worse, to tic on cue. He says Davidson found the experience uncomfortable, too.

“I did have trepidation, of course I did,” says Aramayo. The actor’s union Equity recently criticised the casting of a non-disabled actor in the lead role of a new production of The Hunchback of Notre Dame, while a 2025 study found that 80% of disabled characters on TV are portrayed by able-bodied actors. When asked how he plans to handle any scrutiny he might receive for portraying a condition he doesn’t have, Aramayo chooses his words carefully. “Look, it’s inevitable. But if we’re talking about casting, we’ve got to talk to the director, and to John, and the people who cast me in the role, and I was just really excited to play John,” he says.

Aramayo grew up in Hull in the 1990s. His mother worked in safety clothing, stamping the names on high-visibility jackets; his dad, he says, made sofas. At school, he was a performer who would often impersonate his teachers. “In a naughty way, yeah,” he says with a grin. “I had one Irish maths teacher … I got sent out big time.” When he was nine, he joined Hull Truck theatre’s youth programme. He’d seen his older sister, who was 11 at the time, in Richard Bean’s production of Under the Whaleback, which also featured an actor called Paul Popplewell (24 Hour Party People, Casualty). “I was like: ‘Wow. He’s cool.’” At school, acting didn’t feel like something he could pursue. But with Hull Truck, “that’s when it started to get serious”, he says.

The path to becoming an actor was clear: audition for the London drama schools. “I wanted to do that,” he says, “but at the same time I wanted to try different things.” When he guilelessly Googled ‘Best drama school in the world’, the first result was Juilliard School, the performing conservatory in upper Manhattan. “It was stupid of me,” he says, laughing. “I was, like, 16.”

Two years later, Aramayo was standing outside his new dorm room with his dad and sister when he saw two American college students with blue wheelie bins, running towards them at speed. “They were screaming: ‘Welcome to Juilliard!’” he remembers. “It was like they were coming to attack us. We were just three people from Hull.”

Step in the right direction … Aramayo and Kirk Jones. Photograph: Gareth Cattermole/Getty Images/IMDb

New York City was a culture shock, and an education. Aramayo was reading classic US plays such as Thornton Wilder’s Our Town, and studying Nietzsche. “You were just trying to get your head above water,” he says., insisting that he’s “not an academic person”. Outside lessons, he worked for the university “painting or filing to try to earn some extra money”. His big city dream was expensive. “But it was good for me to learn that, and to survive on a budget,” he says.

His first year out of drama school was so exciting it “blew my head off”, he says. He landed a part as a sergeant in a six-part HBO series about the adventurers Lewis and Clark. It starred Casey Affleck, and involved three months of prep in Canada, in the woods. The production shot for a month, “and then it all went bang”, he says. Production was halted due to creative differences and the series was ultimately scrapped. “I didn’t understand the fragility of it.” Work, he realised, could disappear as quickly as it arrived. But “I got Game of Thrones straight afterwards”, he admits.

Despite appearing in several shows with cult followings, Aramayo insists he rarely gets noticed. When Behind Her Eyes came out, audiences were rattled by Aramayo’s irreverent heroin addict, and the show’s supernatural twist ending. “I had some really funny interactions with people asking why I stole souls,” he says. “I’d say, ‘I’m sorry!’” He chuckles. I warn him that soon, it might start happening again, with all the praise and potential awards buzz for I Swear. Aramayo is not so sure. “You get a flurry of that stuff, and then it goes away very quickly,” he says firmly. “Then you’re back to trying to get a job.”

Aramayo hopes the film will ring true for the many people with Tourette’s he’s encountered during the past year. “I just hope some of them watch it, and they’re happy with it,” he says. And as for Davidson? Jones says when he screened the film for him, “there were lots of hugs and kisses”.

I Swear is in UK cinemas from Friday.10 October.