I’m not sure exactly what I’d been expecting. Years ago, my son had been a huge fan of Hannah Montana and loved the Disney show that shot Miley to global stardom, but when I told him I was heading to the States to interview Miley, he gave an awkward teenage boy grin and blushed.

When Cynthia, our breakfast waitress in Louisville found out we were there to interview Miley, she told us: “I just don’t get it. One minute she’s tellin’ kids to be the best they can be, the next minute, she’s strippin’.”

And refreshingly, Miley was up to the challenge of helping people “get it”. The interview was Miley Cyrus access-all-areas.

Our chat was no holds barred - a rarity for superstars these days. There were no restrictions put on what we could ask Miley. That’s pretty unusual. She clearly knows publicity is part of her gig and she sat down with Sunday Night without a smidgeon of resentment or petulant resigned boredom. Before the interview even began, Miley Cyrus was already different to many celebrities.

Interviewing her, you learn that there is much more to Miley Cyrus than twerking. She talks at warp speed, fitting more words into 30 seconds than most people manage in two minutes. She’s clear skinned and clear eyed, super fit and svelte, seriously smart, with no signs of her drug-fuelled party girl persona. She may even be stepping away from enthusiastic public endorsements of “Weed, the best drug on Earth”, like she gave a year ago in Rolling Stone. There’s a lot of growing up between 20 and nearly 22.

We covered a lot of ground – childhood with her Dad, Billy Ray Cyrus, the man who made mullets king and gave us Achy Breaky Heart, the influence of her Godmother Dolly Parton and Hannah Montana, her Disney alter ego. What she had to say about Hannah surprised me, given that she pretty much took a wrecking ball to her to go solo.

We even made it to Elvis. Miley is convinced Elvis was twerking long before she put it on the map. She also cited The King to have a stab at society’s double standards. “He was a symbol of sex, but nobody would’ve ever called Elvis a slut, because he wasn’t a girl.”

We covered her penchant for sticking out her tongue in photos. Her answer about why is fabulous. We dissected that 2013 VMA foam finger performance and drugs, and Miley was open and honest all the way. No minders stepping in; no shutters coming down.

We got to her breakup with former fiancé Australian actor Liam Hemsworth, and the interview wasn’t stopped. There’s no doubt she found their split tough and like most heartbroken people, took time to rebuild herself.

She gave us a message for the parents of millions of kids who grew up watching her, who are still watching her now as impressionable teenagers. And it’s not what you’d expect from the young woman who blurred the lines last year nearly naked on stage with controversial choreography, a foam finger and a 36-year-old man.

Behind the scenes with Miley, it’s obvious her joie de vivre on steroids isn’t reserved for media and stage performances only. Heading for curtain up with her dancers of all shapes and sizes in tow, Miley clutches a giant slurpee after a meet and greet with fans and marshals the troops with zeal.

Her current tour "Bangerz" kicks off with Miley sliding onto stage down a giant tongue that appears from a lifelike winking image of her head. 100 rows back, you can feel the force of her energy. She executes parental-guidance-recommended choreography with precision, cavorting non-stop through the first three numbers - even singing off-stage through costume changes. It leaves you wondering how she could possibly be fit enough to dance like that and sing so well if she really is the party girl she has claimed to be. I can’t say fitness was top of mind for our cameramen though, they were like goldfish in disbelief over the moves they saw through the lens. It’s pretty clear this is not a girl who’d settle for a meat dress as a gimmick.

For 21 year old Miley, society needs equality, gay marriage, respect for others and their choices. She says her “Bangerz” show is a statement about personal freedom. Her message is live and let live. Whether us oldies think that message is coming through in her execution of it so far, is what has the world talking.

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