But when george, the up-and-coming indie band from Brisbane, helmed by charismatic brother-sister duo Katie and Tyrone Noonan, first heard that Polyserena, their debut album had gone platinum, they were completely stunned.

They were playing a festival in Yallingup, around 250km south of Perth, and held a party that night in the pub.

"It was a huge shock." Katie recalls, 20 years down the track.

"I think we knew that we were onto something special musically, we felt that as a band, that we'd made a unique soundworld. That was our goal and our primary purpose."

And plus, she says, the band had been around for years already.

"The album came out in 2002, and we started in 96, so we were kind of like the six-year overnight success," she says.

When the band's platinum status (more than 70,000 records) was announced, it was only the start of a surreal whirlwind.

The album was played on high rotation, and george was one of the first indie bands to regularly sell out huge venues for their live shows.

"Suddenly we were performing at the ARIAs and all of that stuff, so it certainly was mind-blowing, and no one was expecting that, least of all of us."

She's speaking ahead of a one-off event on Saturday at the National Film and Sound Archive, when she and Tyrone will reminisce about the seminal album.

In the years since, the band - made up of the Noonans, along with Geoff Green, Paulie Bromley and Nick Stewart - have all gone on to do other things, disbanding amicably in 2004. And neither Katie nor Tyrone - both accomplished vocalists - have listened to the band's music much since the Polyserena years, both preferring to look forward to their own solo projects.

But Tyrone says he did sit down with a housemate recently to give it a spin, and liked what he heard.

"My favorite songs are not the singles, they're the more obscure tracks on the record. I think my sister's favourite is 'Chemical Dreams', and mine is 'Strange Days'," he says.

"I can't really find exactly why, I think I'm really happy with the sounds I came up with for that song. And I just remember the day that we recorded that was that one of those days where everything we touched turned to gold."

Gold is the word; the album took Australia by storm and would come to define the year for a whole generation of fans. Not to mention new ones: Katie says her own kids have recently discovered Polyserena.

"My sons are discovering this person that was their mum before they were born, and they're both musicians and so they're getting into it," she says.