It’s the 1970s. Somewhere in the sun-bleached, fake-tanned paradise of coastal Australia, a bunch of kids are effectively raising themselves while their parents flirt, feud and continually fuck up. The kids fend for themselves, learning about sex and adulthood from TV and the terrible influence of their parents’ actions. While mum and dad hold a key party, the kids shoot home stunt movies in which they literally set each other on fire. It can’t end well.

This is Swinging Safari, the latest comedy from Stephan Elliott the man who directed The Adventures of Priscilla, Queen of the Desert and the underrated oddity Welcome to Woop Woop. His take on Australia is garish, often ugly and fragile, and always hilarious – this film is no different.

The ensemble cast is a roll call of Australian royalty (apparently when Elliott asks, nobody says no) including Guy Pearce, an unrecognisable Kylie Minogue, Jack Thompson and Asher Keddie.

It’s not set in the ’70s per se. Instead, it’s set in the mists of memory, circa the collective memory of that decade. Men with handlebar moustaches spill fondue on the shag carpet at a suburban key party. Fake tan abounds. Magpies swoop on unsuspecting skulls. It’s how Elliott and the cast remember things. Sort of.

Ahead of the release I meet up with Elliott and Keddie at their hotel in Melbourne. Their laughter fills the room. They’re still buzzing from the collaborative process of making the film. I don’t need to do much. I throw out the odd question and watch it ricochet between them.

They worked damn hard on this film, as they keep reminding me. But they also had the time of their lives.

“So we walked outside, you lot dressed in these dreadful fucking outfits,” says Elliott.

“Oh god,” says Keddie.

“We walked through the streets of the Gold Coast, and no one blinked. No one cared who anyone was. This woman walked past Radha Mitchell, who was completely chocolate brown, and said quietly, ‘Well she’s gone a bit far on the tan.’”

“A bit,” screams Keddie.

I venture to interrupt with a question: so why dig up the past now?

Elliott sighs. “As I race towards my 60th year and the marbles begin to drop…”

“You’re not racing,” says Keddie.

“I am,” he says. “I started in this business at age 14, whether I like it or not, I’m on the way to 60. I’m an elder statesman.”

With that comes reminiscing, and the urge to do something creative with his memories. “I needed to get this down before I start forgetting. My partner says, ‘You’re beginning to repeat yourself, and miss a punch line or two.’”

Elliott says Swinging Safari is about answering the question: “How did you turn out like this?”

“And the answer is the lost decade of the ’70s.”

Lost? In what sense is it lost?

“The ’60s were extraordinary: the sexual revolution, wars, society reinventing itself,” says Elliott. “The ’80s brought cheap airfares and the beginning of the internet … we became part of the world. What happened in the ’70s?”

Um… disco?

Saturday Night Fever came out here in 1978. What happened before that?”

So, in the interest of historical accuracy, Elliott and the cast put their heads together. They scoured their family albums for visual clues to aid their memories. The results were shocking.

“It looked … pretty bad,” says Elliott, before repeating: “Pretty,” he says, “bad.”

Their childhood memories of glamorous, endless summers were wrong. The clothes were appalling. The food was worse. The times were toxic – and not just the flammable polyester shirts and the pool chlorine. So they amped up garish colour and poor taste, and turned it into a riotous collective memory of youth.

“Well,” Elliott says, “who wants to see another really ugly Australian film?”

He and the cast spent a week together work-shopping their own memories. Keddie says her character, the highly-strung Gale, is largely based on her own mother. “I got that flicked hair look,” she says. “I looked in the mirror and I looked just like her. I sounded like her too. I got her laugh right – that brittle laugh.”

And did her mother really urinate on neighbourhood children who’d been stung by jellyfish?

“No, that was my mum,” says Elliott.

Right.

“I mean, I have no memory of it. Maybe I blocked it out,” he says, shrugging. “No wonder I’m gay.”

Lizzy Gardiner, the costume designer, shines. From what ends up on screen, she seems to be having the most fun she’s had since she brought drag glam to the desert in Priscilla.

“Well, she still worked her guts out,” says Elliott. “Those clothes just don’t exist anymore.”

“But she did have a lot of fun pulling it together with the actors,” says Keddie. “Me and Lizzie laughed until we cried making these choices.”

“I remember seeing that pink jumpsuit and saying, ‘Oh girls, are we really doing this?’”

“And we said, ‘yes, we’re doing it’,” says Keddie.

“If you have great people, let them do their jobs,” adds Elliott. “You were the one that had to wear it.”

The whole film, like the costumes, is a collage of beautiful ugliness and gloriously poor decision-making. The plot of the film is a secondary concern. Like the product of the eager teenaged filmmaker main character (who Elliott considers to be himself), the film is a scattered series of vignettes held together with love, affection and enthusiasm.

“The adults in the film are lost,” says Keddie.

“Lost, and looking for a skerrick of a clue,” adds Elliott. “Everyone’s looking for a plot.”

“But there’s real pain in it,” says Keddie. “The kids don’t feel safe. They’re lost, because their parents are.”

And that’s pretty much how Elliott remembers it.

“The line is in the film: do we rewrite history?” says Elliott. “The answer is, probably. Because god knows our parents would. Oral history is interesting. We all adjust our memories to justify ourselves. I’ve tried to be really honest.”

“I ask my mum now, ‘What were you doing?’” he says. “She said, ‘To be perfectly honest, we were just doing what everyone else was doing.’ They just kept up.”

Swinging Safari is released on January 18.