With the runaway success of Bohemian Rhapsody, detailing the lives and loves of Freddie Mercury, it was more a matter of when, not if, the equally flamboyant Elton John would have his fairytale recited.
Rocketman is the explosive, razzamatazz result and, like Bohemian Rhapsody, will surprise and delight the icon's aficionados, as it lifts the lid on Elton's turbulent early life and success.
"It's a warts 'n' all exposé," acknowledges Richard Madden, who plays Elton's first lover and former manager, John Reid. "We really get into all the different elements of him; his vulnerabilities, his nastiness, his outrageousness – you really get the whole journey with this.
"But it shows everything in a fictionalised, interpretative way," adds Madden, explaining the fantasy biopic. "We go into these abstract sequences that have a real Moulin Rouge feel to them, where suddenly you're into a big song and dance number. It's all a bit surreal! That's what made it really exciting for me though because we can really explore the extremes of Elton's life through these larger-than-life numbers."
Likewise, for Taron Egerton, the chance to portray Elton John in Rocketman was both exhilarating and daunting - mainly because he was singing every song in the film himself.
"When Jamie Foxx played Ray [Charles], they used Ray's vocal, when Rami Malek played Freddie Mercury, they used Freddie's. But I didn't want to lip-synch. That didn't appeal to me," he asserts. "I decided if I was going to play Elton John then I had to sing – and sing it all!"
So he does. But Egerton admits that he did have moments of self-doubt, where he agonised over what he had got himself into.
"Although part of the joy of this project was the singing, which I love doing, it's been quite a learning curve. I've never had so much demanded of me," he concedes. "Also, it's nerve-racking playing an icon because everyone feels quite a strong sense of ownership over his work. So, although I wasn't that nervous about doing Elton, I was really anxious about people accepting my take on him."
In contrast, Madden admits he was incredibly nervous about having to sing and perform in some of the fantasy scenes between his character and Elton. He even had second thoughts about playing the role of John Reid.
"When we did the read through I noticed that 50 per cent of the film was song numbers, and I was like; 'Shit, half my job is to tell the story through song and dance!' I'm not a karaoke king - it's not my natural habitat to sing and dance – so I was really terrified," he admits.
"But I realised how important these songs were to telling the story because through a three-minute song we can cover three years of their life together. So, although it was a challenge for me, when I put it in that context then it became something really exciting, fun and challenging. But thank God for auto tune, that's all I'll say!"
One of the stories that is woven into song is how John Reid and Elton John met, fell in love and started a torrid five-year relationship. It's a fantasy performance which involves an intimate love scene between Madden and Egerton - the first time a major Hollywood feature has shown gay sex on screen.
"Sex scenes are never fun to shoot and I only ever do these things if there's a real justification for them," reveals Madden. "This was the first time Elton ever had sex with anyone, so that's why it's a relevant scene. It played a really big part in the birth and progression of their relationship and it's as true to fact as we could be with where it happened, how it happened and when it happened."
Making everything "as true to life" as possible was abetted by Elton and his husband, David Furnish, being fully on board with Rocketman, as executive producers. It might have made exposing all the darker shades of Elton's troubled past problematic but, as Egerton recalls, he gave them his full blessing.
"Elton was very hands-off, which I'm grateful for because I would have found it very difficult if he'd come on set while we were filming," admits Egerton. "He never did – not because he wasn't welcome – but because he's a very sensitive, creative person and I think he knew that I'd find it too much.
"There was a day that David came on set with their two boys though, and that was a very surreal moment," he adds. "I was in full Elton John makeup and costume, from when he was in his 40s - so not a million miles away from him now – and his kids were staring at me, like I was their daddy. It was bizarre.
Equally bizarre, he admits, was getting an invitation from Elton to spend some time with him and his family on holiday. It's a moment that Egerton recalls fondly, one which cemented his commitment to Rocketman and bolstered his admiration and respect for the icon.
"I was fortunate enough to go and stay with him last summer and he let me read his diaries. I was there with my girlfriend, sitting by his lake – he has his own lake, for God's sake - and there are entries like, 'woke up this morning, did the laundry, wrote a song called Honky Cat...' It was mad," he says, shaking his head in disbelief.
"The diaries were [written] in biro and I remember thinking; 'If I lick my finger and rub the biro I could erase all these memories!' It was a crazy thing to think, I know, but it made me realise what I was now a part of.
"It may be a very grandiose thing to say but to be a part of that legacy, which I guess in some respects I will be, is just the most amazing thing ever."
LOWDOWN:
Who: Richard Madden and Taron Egerton
What: Rocketman
When: In cinemas May 30
'The truth of what happened has never been told.'