Australian actor Jack Thompson had a little-known 15-year relationship with two sisters.

Australian actor Jack Thompson was Cleo’s first ever nude male centrefold…and the absolute heart-throb of the 70s.

He was today’s Liam Hemsworth – loved and admired by all.

He has worked on close to 50 films over his career including The Man From Snowy River, Star Wars, The Great Gatsby, Australia, Spyforce, The December Boys and Blinder – to name a few.

But for a man with such an impressive career and prominent place in Australia’s cinematic history, many might be unfamiliar with Jack’s past love life.

For 15 years in the 70s and 80s, he was in a relationship with two sisters.

Here is a snippet from A Current Affair of Jack and the sisters talking about that time in their lives. Post continues after video.

The youngest of the pair, Bunkie, was just 15 years old when she joined her older sister Leona, then 20, in a polyamorous relationship with the actor.

At the time, Thompson used his relationship with the sisters to boost his image as a sex symbol promoting the arrangement as “mutually beneficial” and one built on the foundation of love and respect.

But years later in a memoir titled Somebody That I Used To Know, Bunkie King revealed just how much damage the set-up caused her.

At the time their love affair was sparked, Bunkie King says she was a "flat-chested scrawny teenager who had never even kissed."

A few weeks after meeting Jack at her sister Leona's birthday party in 1969, he turned up at her family home while she was on school holidays and invited her to a party.

But her mother said no, on the premise it would be too adult.

So Jack continued to visit instead - to chat.

The inexperienced teenager fell head over heels.

Meanwhile, Jack and older sister Leona were getting serious. They'd moved into a share house together just behind Bunkie's family home - and so a relationship between both sisters began, simultaneously.

"Le works shifts at a restaurant, sometimes from 2pm until midnight, which gives me the opportunity to spend time alone with Jack.

"One night we were kissing and cuddling in their [Le and Jack's bedroom] and Le bursts in the door and starts yelling, 'What the hell are you doing?'," Bunkie told the SMH.

The next day Jack and Leona came over to "discuss the situation."

It was Jack that suggested a three-way relationship.

"The fact is, I love you both," he told them.

And so they did. Sharing Jack on alternate nights.

Off the back of his starring role in the TV series Spyforce, Jack bought a property in the hills above Coffs Harbour in NSW, and the trio moved in together.

"He alternates nights between Le and me so there's no favouritism," explained Bunkie of their arrangement.

Sadly, the two sisters barely talked as the relationship continued. Bunkie describes how she continued to feel "guilty" throughout it for moving in on Leona.

In an interview with The Herald in 1972, the trio did an interview about their relationship, in which the journalist asked the women how they could share one man.

"We don't feel like we sharing Jack. He doesn't belong to either of us, so we can't share him. We don't own him, but we do love him. We are sharing time and life with him," was Bunkie's reply.

In 1974 another article, this time in the Daily Telegraph chose the headline; "Jack and his Jills." In it, Jack claimed he occasionally felt "like a bone being fought over by two dogs."

Over the coming years, a young Bunkie would slowly start to question herself.

In 1984 she remembers thinking; "What am I doing with my life? I have no money, career or family close by." She had had three terminations during her time with Jack, but was starting to think that perhaps she would like to have a child.

In 1985 she realised she was living an illusion, and soon after left the relationship during a dramatic fight in Spain at an airport.

It was 2015 when Bunkie finally broke her silence on that period of her life and the details of the relationship - by that point she was a 60-year-old mother of two.

She decided to write about her story when her son blurted out; "I'm not proud that my mother had sex with her sister."

As Bunkie explains, that never happened, so she decided to set the record straight.

Looking back, Bunkie thinks her relationship was in fact "quite old-fashioned."

"We had separate bedrooms, he was just sleeping with both of us," she told New Idea.

"In some societies, a man has a wife and a mistress, or maybe a couple of mistresses. But it is unusual in Western society... I was captivated by his attention," she told A Current Affair in a sit-down chat.

In 2018, Jack's life took a new turn, after he was admitted to hospital with kidney failure.

He was told he was 48 hours from death, and so began dialysis three times a week for five hours - something Leona, now his wife of over 50 years, helps him with.

"I am eternally grateful for her friendship, her company and her love. I am eternally grateful for that," he told New Idea in 2021.

"Yes, I would call this a great love."

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