Heartfelt dramedy The Truth is a landmark moment in French cinema – and not just because it brings together national living treasures Juliette Binoche and Catherine Deneuve on screen for the first time.

Wryly sending up her diva reputation, Deneuve plays Fabienne, a demanding movie star.

Binoche is her estranged, exasperated screenwriter daughter Lumir, visiting from New York with her frustrated actor husband Hank (Ethan Hawke) and cute young daughter Charlotte (Clémentine Grenier).

Connecting with Australian audiences, where it just soared past $800,000 at the box office, what makes this very French family argy-bargy even more remarkable is it’s by renowned Japanese writer/director Kore-eda Hirokazu.

The follow up to Shoplifters, for which he won the top prize at the 2018 Cannes Film Festival, The Truth is his first movie shot outside Japan.

France has very different rules and regulations around filming, presenting some challenges. Oh, and he doesn’t speak French.

It all came about when Binoche called him out of the blue.

“I’ve been a fan since her early work, so it was a big surprise for me,” he chuckled. (We’re speaking through a translator at Palace Cinema Como in Melbourne.)

Wearing a navy cardigan and unbuttoned white shirt, he says Binoche and Deneuve are both surprisingly easygoing.

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“The thing they have in common is that they’re very frank and up front about what they think, and what they want to do,” he said with a smile.

Deneuve certainly lived up to the rumours on set, but Kore-eda, ever the gentleman, insists he loved her unpredictability.

“We’d start at about 10 in the morning, and I’d get together with the cast and crew and talk through my storyboard for the day, and that will get us to about 11ish,” he recalled.

“Catherine would put a call in to say what time she thinks she’ll come, which is supposed to be noon, but of course, she turns up at around 1pm or 2pm.”

Catherine Deneuve’s energy gelled with Kore-eda’s passion, the director said. Photo: Palace Films

They’d hash out her lines while wardrobe was doing her hair and make-up, with Deneuve offering plenty of input.

“She likes to work in a live and organic way, and I do as well, so we were very well suited to each other,” Kore-eda said.

“I don’t understand the meaning of each word, obviously, so I would listen to the rhythm of the language, the tempo with which they would throw dialogue at one another during each take and get a good feel for it.

“The way Catherine does things, she’s very mellifluous and lyrical. It’s like music.”

Transfixed and super happy, he’d turn to his translator only for them to say, “Yeah, that was great, but she totally messed up the line”.

Chuckling again, it’s clear there’s no ill will, only respect.

There’s a magnificent moment in the movie when Fabienne storms out of a shoot and Lumir thwarts her escape as their stand-off thaws.

Kore-eda says it was magic behind the camera, too.

“Catherine turned up late that day and I thought maybe we’d have to push the scene to another day, but she said, ‘No, no, we’re going to do this’.

Deneuve and Juliette Binoche came together on screen for the first time under Kore-eda’s hand. Photo: Palace Films

“So she pulled her skates on and we did the scene in one take. And she just nailed it. That was really cool. Out of the blue she just comes out with 100 per cent.”

He’s used to strong-minded women, picking up his love of cinema watching old Hollywood movies, French classics and the works of Italian great Federico Fellini with his late mother.

“After she got married and had me, there wasn’t as much money, so she didn’t go to the cinema often,” he recalled.

“We’d watch movies together on television on Sunday afternoons and, of course, all the voices would be dubbed, but I didn’t really enjoy it.”

Why on earth not?

“She had a mean streak and she’d just call out the ending while you were really into a Hitchcock,” he laughs.

Director Kore-eda Hirokazu follows up his Cannes winner Shoplifters with The Truth – in French. Photo: Palace Films

When she died 10 years ago, it had a significant impact on his filmmaking, Kore-eda says.

“When I started out, I always considered how my film would play internationally. But when she passed away, I made Still Walking, which was a deeply personal story. I wasn’t thinking about the world, I was digging very deep into myself.”

His distributor worried it wouldn’t play well overseas, but it turned into his breakout hit.

“And so the conclusion I drew from that is that if you dig deep enough in one spot, you come out at the other side of the planet.”

Ain’t that the truth?

The Truth is in cinemas now