If ever there was an actor who seemed in danger of being trapped by a role, it is Daniel Radcliffe. After playing Harry Potter in eight movies, there cannot be many places on the planet where his name is not associated with the Hogwarts hero. But Radcliffe is refusing to be boxed in, as his new film, Kill Your Darlings, amply demonstrates.

It is all a matter of attitude, he says, when we meet in London. Potter had been “the most incredible opportunity in the world as a start to a career. For me, that’s the only way you can see it,” he explains. “Because otherwise, it becomes whatever everyone else seems to want to see it as, which is a handcuff or a hindrance.”

That he even thinks about such things is refreshing. Having become a multi-millionaire in his teens — and reportedly worth over £56 million today — fame and fortune could have sapped him of his motivation. Or worse, made him lose his head. Yet Radcliffe comes across as ambitious and grounded, and appears, I tell him, to be using the freedom afforded by his wealth to make daring decisions, heedless of the risk of failure.

“I’m in a position of financial security where I can go off and do whatever I like,” the 24-year-old agrees. “I don’t have to do something for the money. I can do things purely because I want to do them and I am passionate about them.”

On stage, this has meant bold choices such as the role of a horse-mutilating stable boy in West End and Broadway productions of Peter Shaffer’s psycho-sexual drama, Equus — a part that required him to appear nude. He was 17 at the start of the London run and had three instalments of the family-friendly Potter saga still to shoot. Surely the studio must have been worried?

“I suspect there were a few ‘He’s doing what?’ conversations,” Radcliffe admits, laughing. “But they definitely settled down pretty quickly.” For him, the play was “a huge thing, because it sent a message to the industry that I wanted to push myself and challenge people’s expectations of me”.

And if his performance in his first post-Potter film — last year’s The Woman in Black — did not quite convince moviegoers and critics that Radcliffe had left Harry behind, then his sensitive portrayal of the gay, Jewish-American beat generation poet, Allen Ginsberg, in Kill Your Darlings should silence the naysayers.

“I think The Woman in Black was a transitional film, for me,” he says. “I wasn’t ecstatic about my performance in it and I felt there was a long way to go.” He shot the movie a month-and-a-half after finishing the last Potter, “so when I watched it, I still saw a very similar physicality in the performance to what I had given in the past”. Portraying Ginsberg was more of a “step away and shows more of a range than people have ever seen me do on screen before”.

Kill Your Darlings takes place in and around New York’s Columbia University in the 1940s, when the ground-breaking writer was just finding his voice — and awakening sexually.

It tells the story of a murder that helped shape him and fellow beat icons Jack Kerouac and William Burroughs. Ginsberg was the only Jew among them and the film’s director, John Krokidas, worried about a non-Jew playing the role. He was, therefore, suitably delighted when Radcliffe told him that his mother Marcia — born in South Africa, raised in Westcliff — was Jewish.

For the actor, it was unimportant. “We’ve had plenty of non-Jewish actors play Jewish characters now, and vice versa,” he says. “But I think John was aware that there was a certain part of the Jewish community in America that might baulk at the idea of me playing Allen Ginsberg. So I think he was relieved that I have Jewish blood and he could say: ‘No, no, no, he’s Jewish!’”

Radcliffe is not religious, however, and, in fact, decided, aged 14, that he was an atheist. Even so, he remains “very proud of my Jewish parentage. But I know that there are people in the world who devote their lives to being Jewish and Judaism. So I like to say I’m Jewish by race rather than faith.”

His father is a Northern Irish Protestant and he says that if anything is shared in his parents’ roots, “it’s very hard-working blood”. It was “a very different” background to many of his peers at school (Sussex House, Chelsea, and City of London). “A lot of them will receive titles at some point in their life. And I sort of got a sense, from going to friends’ houses, that my parents were decidedly more left-wing than most of their parents.”

Although he felt that he did not fit in, “I didn’t dislike myself for it. I was like: ‘There will be somewhere where you fit in.’ And, luckily, I found it a lot sooner than I was expecting.”

Radcliffe was nine when he was cast as the young David Copperfield in a TV adaptation of the Dickens classic. “I remember sitting on set for those first few days and just being like: ‘I have arrived. This is it.’” Whereas he had often got into trouble at school for talking too much and being hyperactive and easily distracted, “on set, I found that I didn’t have any issues with distraction. And my energy and the fact that I was friendly and liked chatting to people were all good things, rather than bad things. I think that gave me confidence that I would have been stripped of had I been through school during my teenage years.”
It is perhaps no coincidence that he seems to specialise, by his own admission, in characters that are “on the fringes of something”. Ginsberg — a gay Jew — is one. His sexuality features prominently in Kill Your Darlings, and Radcliffe’s appearance in a sex scene with another man has been feverishly documented. However, the “shocked” tone of some of the reporting has dismayed the actor.

“I may be speaking out of turn,” he says, “but it’s sort of the acceptable face of homophobia. If a man was getting asked questions about a heterosexual sex scene, people would just be saying, if they asked at all: ‘How was the scene?’ Not: ‘How was the straight sex scene?’

“It’s because of me being associated with Potter that it speaks to a very puritanical value — that we don’t want our kids to even see somebody they admired playing a gay character. That that is an issue for people is pretty terrible. We should really all be growing up.”

And also moving on, because Radcliffe certainly is. He has now been cast as Sebastian Coe in a film about the athlete’s rivalry with Steve Ovett, and will play Igor to James McAvoy’s Frankenstein in a new take on the Mary Shelley novel.

Meanwhile, he has a dark fantasy feature, Horns, and a romantic comedy due for release. Oh, and a new series of the darkly comic A Young Doctor’s Notebook, co-starring Mad Men’s Jon Hamm, which is currently being aired on Sky Arts.

All of which begs the question: Harry Potter who?

Kill Your Darlings is released on December 6