Rupert Grint: I struggle to remember life before Harry Potter

Grint, co-starring this Christmas with John Malkovich in The ABC Murders, isn’t entirely at ease with the ten years – from 2001 to 2011 – he spent as Weasley, alongside Watson’s Hermione Granger and Radcliffe’s Harry Potter. “I struggle to remember life before it,” the 30-year-old says. “I think I lost myself a little bit along the way. With the fame, you’re almost being the character even when you’re not in character.”

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The unease is there to see when he walks into a Soho hotel. He’s jammed a black baseball cap down on his head and wears black jeans and a black sweatshirt emblazoned with a large white skull motif. “I like the dark side,” he says, nervously folding his gangly limbs into a high-backed chair. “I’ve always been into crimes and murderers. That side of humanity has always interested me.”

Grint talks about darkness a lot. He “loved the very dark” script for The ABC Murders, in which he plays Inspector Crome – “someone with authority,” as he puts it. “I’m used to playing the vulnerable, nerdy sidekick.” And he admires the way Malkovich, as Hercule Poirot, “brings this quite psychotic darkness”.

Grint also talks about his art, the times he disappeared with paper and pens to draw during his decade as one of the three most famous children in the world. “I’ve always drawn,” he says. “It’s cartoony, doodles really, but I find it very therapeutic. It’s quite dark, and a bit weird.”

At the age of ten, Grint was lifted out of his childhood and placed at the heart of a movie franchise that generated $10 billion. It’s been seven years since he appeared in the final film, Harry Potter and the Deathly Hallows: Part 2, but for millions of people under the age of 40, Grint is still Ron Weasley. “From the moment I got the part, my life completely changed,” he says. “It was a weird time and it has taken me a long while to process. Just being invisible can still be difficult. Sometimes you just want to go to B&Q.”

For the past six years Grint has been in a relationship with the actor Georgia Groome. He says it’s natural to date people from his own world, “who have that kind of understanding. It definitely helps. It’s not like being in One Direction, but there’s always something, every day, even with my hat on. It’s never calmed down.”

Grint suits the 1930s costume of The ABC Murders. The instantly recognisable red hair is slicked back, he’s replaced the fluff that long lurked on his upper lip with a proper moustache and he more than stands his ground against the mercurial Malkovich. “I never feel like I’m the most famous person in the room, but I think I’m quite at ease with other actors – Malkovich was different. I was nervous around him, because I’m a huge fan.”

Grint was good in Sick Note, “the show about a man pretending to have cancer, with Nick Frost” and good also in Sky’s TV version of Snatch. Why hasn’t he done more? “After Potter I didn’t really know what I wanted to do,” he says. “I had this feeling that I had missed out on normal things. I lost touch with a lot of my friends from school. I wanted to have a bit of a life again, so I took a break.

“I’ve never really been super-ambitious. I think there’s always been something in me, particularly when I finished Potter, that wants to prove myself, but I’m also naturally quite an insecure person anyway.”

Grint was born in Essex. His father, a dealer in racing memorabilia, handled the meeting with lawyers when he first signed up for Harry Potter. Rather than worry about himself, Grint says his main concern has always been for his younger siblings: James, Georgia, Samantha and Charlotte. “It was a struggle for them,” he says. “They got a lot of attention at school.”

Did he feel guilty about that? “Yes, a little bit, because it wasn’t their decision. It was my choice to do this thing and it’s affected everyone in a different way. Not always in an unbearable, negative way, but it’s quite a strange existence sometimes.”

Still, the experience has made him very wealthy. I tell him one newspaper valued his wealth at £28 million. “I actually don’t know how much I have. I couldn’t even really guess.” Doesn’t he count it? “No. Not really. It doesn’t really motivate me too much. It makes you comfortable, that’s the good thing about it, I think. I’m glad it’s there but I’m not really that focused on it.”

Daniel Radcliffe addressed the question of how to leave behind the character that made him famous as early as 2007 when he appeared naked on stage in Peter Shaffer’s disturbing psychosexual drama Equus. In his own way Grint has also tried new things, appearing on Broadway with Matthew Broderick in the farce It’s Only a Play and playing an amphetamine-using gangster in Jez Butterworth’s 1950s-set Mojo in the West End. “It was draining emotionally and physically,” he says. “I didn’t really foresee just how draining.”

He still occasionally compares life notes with the other two Harry Potter stars, Radcliffe most recently in New York. “We have those chats,” he says. “Definitely. Because we’re all carving out very different journeys. And we have this shared experience that connects us all. They are the only people that really understand. I think David Yates [the director of the final four Potter films] once said we’re all like astronauts. Only astronauts really know what it’s like to go to space.”

Grint says he now finds it hard to watch the Yates-era Potter movies. “I think those early ones are OK. More time has passed. I can detach myself a bit more from that kid. I did see Harry Potter and the Philosopher’s Stone not long ago, for the first time since the premiere, and I actually enjoyed looking back. But the more recent ones I definitely couldn’t do.” Which film would be the cut-off point, after which he could watch no more? “I could probably go up to [third film] Harry Potter and the Prisoner of Azkaban.”

What was the first thing he did when he was finally free of Harry Potter? “I had my tonsils taken out. I had massive tonsils, I could feel them. And it affected my voice. I got tonsillitis all the time.” Had the producers asked him not to have the operation? “Yes. It was too much recovery time and there was the fear that it would change my voice.”

Did he ever stand up and rebel against such close monitoring of his life? “Definitely, around midway. I don’t know if it was a teenage rebellion, but it all seemed too much. It was just exams and things, juggling.”

As the series progressed, Grint got older and naturally asserted himself. “I was really into indie bands like Arctic Monkeys and I would go to gigs.” He could have had backstage passes to any show in the world, but he wanted to be like other teenage boys, thrashing around in the crowd. “I was quite determined in that way not to hide from it; I never wanted any security, or anything like that. I just went in. It was important for me to go.”

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How did he avoid being recognised? “I’d wear animal masks! Festivals were the worst because you’ve got this mass of drugged people, who just don’t care what they do. Once I got picked up.” Picked up off the ground? “Yes, by a group of lads. They were on a stag do. They picked me up and just carried me around for a bit.”

Every time he went out for a drink, Grint had to consider whether he should have another. “It was hard, obviously, when we were in the thick of it. There was always a fear that you couldn’t go too crazy. Was this – having a party life – irresponsible? I’ve always been quite shy anyway, but the whole experience made me a little bit introverted.”

Grint has heard first-hand what it’s like when young careers go wrong – he worked with former child star Lindsay Lohan, who has struggled with drink and drugs, on Sick Note. “Her history is fascinating. I guess the difference is we didn’t film Harry Potter in Hollywood. It was in Watford. But I often feel like people were waiting for it to happen, they were ready for us to step out of line. It didn’t come to that for us. I guess having a really good, strong family had something to do with it. But, yes, at times you definitely felt like it was thin ice. You could easily have gone wrong, in lots of different ways.”

As he pulls his hat back on and prepares to brave the street outside again, I ask Grint if, in the end, he wishes he hadn’t played Weasley. “That’s always been in the back of my mind. What would have happened if I hadn’t got that part? I was always into art, I guess I would have gone to university… I’m not sure, but I do think about that a lot.” He might have been an art teacher at an Essex comprehensive rather than a multimillionaire? “I’d be happy with that."

The ABC Murders will air over three consecutive nights at 9pm on BBC1 this Christmas, starting on Boxing Day (Wednesday 26th December)