It’s every fan’s dream – I’m in Jason Donovan’s hotel suite. We meet ahead of his touring show – Priscilla, Queen of the Desert. I sit down on the brown leather sofa where a copy of the Metro free newspaper lies abandoned, its front page headline screams “Kylie Charged” – a reference to Kylie Minogue, Donovan’s former co-star and inamorata. Fortunately, it’s not a scandal, merely a reference to Kylie switching on the London Christmas lights.

Scandal is part of the Jason Donovan brand. In the 1980s, thanks to Australian daytime soap Neighbours, the toothsome heartthrob was a family favourite, before he nearly blew it all and went on to reinvent himself.

His lowest point was when he had a drug-induced collapse at Kate Moss’s 21st birthday party at the Viper Rooms on Sunset Strip. He nearly died. But that’s ancient history. It’s Priscilla that tremulous fans want to hear about.

The world has changed immeasurably in the 20 years since the Aussie independent movie The Adventures of Priscilla, Queen of the Desert, on which the musical is based, was first released. It was described as a “brash and liberated” road trip taken by three lip-synching drag queens (one gay, one bisexual and one a transgender woman) who cross the Australian desert in a pink-painted bus named Priscilla. It’s a mark of how society has moved on that this remarkable film, an unblinkered look at sexual identity and homophobia, is now family entertainment.

Donovan’s career has also had a radical trajectory. After Neighbours, which once boasted 20 million viewers, he and his co-star Kylie Minogue released a Stock, Aitken and Waterman pop record exploiting their clean cut good looks much as Donny and Marie Osmond had done ten years before. Jason comes from a theatrical family and he was a child actor. Jason and Kylie proved to be a winning combination and he seemed to have the world at his feet. He had a solo career and albums sold by the million. He was a big hit in an Andrew Lloyd Webber musical which earned him footballer’s wages. He was partying hard in London and LA, then it came crashing down.

Donovan has been painfully honest about his life in interviews and his autobiography. His mother had walked out when he was only five and by the age of 27 he could feel his looks fading (the ravages of heavy drug-taking didn’t help). Just like the movie A Star is Born Kylie’s career went stratospheric as his stalled. If nothing else, Jason Donovan is one of life’s survivors.

In a curious twist of fate, Donovan missed out on the chance of a role in the original movie. In a supremely uncool move, he had sued the style magazine The Face when it published a photograph suggesting Donovan was gay. The out and proud movie Priscilla would not have been the best next career move and the part went to fellow Neighbours actor Guy Pearce.

But that was then. In 2009, when Donovan first took the lead in the musical version of Priscilla, it was a huge success. The role of Tick is a part he clearly loves, hence this year’s Christmas revival in Edinburgh.

The original film was edgy. I ask if the stage version has had its rough edges smoothed over.

“It’s got a lot of edge,” he says adamantly. “Films can date but the musical is in many ways a better piece of creative product.” He goes on to add, “The film is of its time. A lot more thought has gone into the musical. I know Stephan Elliott [who directed and wrote the screenplay of the film and the book of the musical] very well. He wrote the film in only eight days. It was a big pop video, but done very well, with a great story and characters. But you can’t put on a stage musical and last the way this has lasted without it being a very fine-tuned thing. Audiences are not stupid. They vote with their dollars. If they don’t like something they wouldn’t come.”

To an extent the movie brought the art of lip-synching to the mainstream, but Donovan points out that a lot of today’s drag artists now sing their own songs “and that’s reflected in the musical. Besides, with TV programmes like Australian Idol and American Idol people expect to hear performers sing.”

Jason sits back. He’s relaxed in a pale shirt, dark jeans and tan boots that tap the floor as if he’s desperate to get on stage and do his thing. This new tour has had some tweaking along the way. “The story is the same but we’ve cut one scene at the end.”

He concedes that the role of Tick is a glove that fits. “The show is well produced, it’s a musical, it’s Australian, it’s my age group… I know this part well. I feel comfortable. I’ve learned that if things are going well… stay with them,” he says meaningfully.

He recently toured with The King’s Speech which shows that he can do more than just song and dance. But Priscilla has almost defined him. I ask what makes the show so popular. “It’s the music… As much as people love The Lion King and Phantom of the Opera, there is a whole new breed of musicals out there and I think – with all respect to Andrew Lloyd Webber and Cameron Mackintosh – there’s a different appetite. Priscilla is dangerous and edgy and it’s family friendly too. And that’s a really difficult trick to pull off.”

Is it great fun? He pauses, raises an eyebrow and laughs. “Eight times a week?” But he’s done up to 1000 performances of Priscilla “and I don’t do that unless I’m enjoying it. Otherwise it would be torture.”

Priscilla, Queen of the Desert is @ Edinburgh Playhouse from Tue 15 Dec 2015 to Sat 2 Jan 2016