Taron Egerton "fell in love" with Sir Elton John while preparing for 'Rocketman'

Taron told The Wrap: "It's nice to have an organic conversation about attitudes and feelings, and certainly about the primary characters in the film. And I was wanting to know about his drug use, and how that first started and how it evolved. And his other addictions: alcohol, eating, smoking weed … He has voracious appetites for all things, as he says pretty much the first thing in the movie. He's one of those people who just can't get enough of anything, whether it be art, work or Class A drugs.

"But more than that, we really sort of fell in love as friends. I think that really informed and fed into my portrayal of him because I cared about him."

Taron also explained he is happy the movie is a glam-rock fantasy and it is one of the main reasons he wanted to star in the film.

He said: "It's a perfectly valid way to tell the story, to strive for total authenticity. That's what a biopic is, and there are some absolutely wonderful ones.

"But that's just not what this film is. Reading the script the first time, it was like, 'Holy s**t, this is cool.' At the core of it, it's got the fundamentals of Elton's journey right. But we absolve ourselves of responsibility to complete accuracy with the tone of it. Elton wrote a really lovely line in an article. He said, 'Not everything in the film is fact, but it is the truth.'

"Once you are existing in a world of fantasy, you're no longer trying to claim that it is set in the exact same universe that Elton occupied. So I can tailor the character to fit our purposes.

"Of course, you never want to go too far away from it, because we're here to celebrate Elton. But you know, the fact of the matter is that Elton and I don't look alike. We trust in the fact that people willfully suspend their disbelief in storytelling, and I just wanted to capture the showman in him, the anger in him, the pain and vulnerability, and trust that when it's all put together, it will feel like Elton John."