Listen up, knuckleheads, if you tend to talk during movies, do yourself a solid: pipe it down.

At least when you’re watching Hirokazu Kore-eda’s Look Back. (Then again, you shouldn’t be talking in the first place — it’s Cinema Etiquette 101!)

You need to pay attention to its soundscape, especially the strangely soothing sound of a pencil scratching against paper. It’s an almost ASMR-like effect.

But who knew capturing that seemingly simple sound could be so complicated?

Sound, as it turns out, is one of the little details that required special attention in Look Back, the venerated Japanese auteur’s latest film, an adaptation of an unusually tender manga by Chainsaw Man creator Tatsuki Fujimoto .

The film recently had its Southeast Asian premiere at the Singapore International Film Festival, where Kore-eda was also presented with the SGIFF Cinema Honorary Award.

It follows two schoolgirls, the confident Fujino (Furi Nanase and Natsuki Deguchi as an adult) and the reclusive Kyomoto (Rokka Okada and Aju Makita as an adult), whose shared passion for drawing manga leads to an unlikely friendship.

Since drawing is their way of communicating, the gentle scrape of graphite across paper becomes an important form of non-verbal expression. (Kore-eda reportedly asked the girls to listen to their pens at work as though it were music.)

Speaking to 8days.sg from The Peony Room at Shangri-La, Kore-eda reveals how he and his sound recording team crafted the film’s delicate aural canvas.

"We wanted to carefully record every single sound," he says through an interpreter.

That included something as specific as the sound of a mechanical pencil making its first stroke on a brand-new sketchbook.

But there was a problem.

Growing up together: Furi Nanase and Rokka Okada (left) share their roles with Natsuki Deguchi and Aju Makita, who portray the older versions of their characters. (Photo: Purple Plan/GV Pictures)

Because Look Back was shot on 35mm (yes, children, film), moving the camera too close to the actors’ hands meant the whirring of the film mechanism could be picked up by the microphones.

While the crew tried to capture as much sound as possible during filming, some had to be recorded separately and added later.

A professional manga artist was even enlisted to recreate the scratch and scrawl of pencil on paper.

And the attention to detail didn’t stop there.

In one particular scene, one character — God forbid, no spoilers — runs her fingers over the lettering on a dotera, a traditional Japanese padded jacket.

Unfortunately, the actual garment didn’t produce much sound when touched.

Talk about homework: Furi Nanase (left, with back facing camera) and Rokka Okada took drawing lessons and received weekly assignments to prepare for their roles as aspiring manga artists. (Photo: Purple Plan/GV Pictures)

So Kore-eda's team recorded fingers brushing against a different piece of fabric with a rougher texture and added the sound to the scene.

At this point, Kore-eda pauses and wonders if he should’ve kept that little factoid to himself.

Too late. The cat’s out of the bag. Well, that's movie magic for you.

But Kore-eda is known for wielding another kind of magic: his remarkable ability to coax natural performances from children.

As evidenced in the child-abandonment drama Nobody Knows (whose then-14-year-old star, Yuya Yagira, became the youngest-ever winner of the Best Actor award at the Cannes Film Festival), the Palme d’Or-feted Shoplifters, and Monster, his young actors often seem wise beyond their years, as though they possess old souls.

So what’s his secret?

Young at art: Kore-eda discusses a scene with Nanase in a scene, often giving the young actress her dialogue before the camera rolled. The director discovered Tatsuki Fujimoto’s Look Back manga during the Covid-19 pandemic and was so moved by it that he decided to turn it into a live-action film. (Photo: Purple Plan/GV Pictures)

For Look Back, it all came down to casting the right actresses: Furi Nanase and Rokka Okada, who were both 11 when filming started.

Nanase was a complete newcomer to acting, while Okada had been in showbiz since she was a baby.

Kore-eda recalls how Nanase, who plays Fujino, arrived at her audition carrying a four-panel manga she had drawn herself.

She proudly showed it off, apparently convinced she was something of a genius. Only issue? Her drawings weren't very good.

But that was okay. It was Nanase’s confidence — and the way she delivered a particular line — that won Kore-eda over.

Back to nature: Kore-eda (far right) and his four leading ladies filmed Look Back in Japan’s northern Tohoku region, capturing the changing seasons over the course of a year. (Photo: Purple Plan/GV Pictures)

Elsewhere, Okada impressed Kore-eda with her ability to convey her reclusive character’s inner emotions. “We wanted to keep watching Kyomoto,” he says. So much so that he expanded her screen time, notably in scenes depicting an imagined parallel world where Kyomoto and Fujino never met.

Filming eventually stretched over 18 months, allowing Kore-eda to capture the changing seasons and the passage of time. Did this approach help the actresses grow into their characters?

Not quite, according to the director.

He explains that Nanase and Okada — as well as Deguchi and Makita, who play the grown-up Fujino and Kyomoto, respectively — had already matched his vision of the characters so closely during casting that he hardly needed to give them detailed instructions once filming began.

For all his gentle humanism and penchant for slow-burn storytelling, Kore-eda is anything but slow when it comes to making movies.

Meet and greet: Hirokazu Kore-eda gets up and close personal with fans at the Oct 24 screening of Look Back at GV VivoCity. (Photo: Singapore International Film Festival)

Before Look Back, he released the AI-themed Sheep in the Box in June. And between features, he somehow found time to squeeze in two Netflix shows, The Makanai: Cooking for the Maiko House and Asura.

If you’re new to the Hirokazu Kore-eda party, the sheer number of titles can be a tad daunting. So we asked the man himself a simple question: Which of his films (or TV shows) would he recommend to a newcomer? (FYI: Yours truly is still playing catch-up.)

Kore-eda says he doesn’t like ranking his own works, but eventually offers three suggestions: Nobody Knows, the 2008 family-reunion drama Still Walking, and 2018’s Shoplifters.

And what if you watch all three and still don’t like his films?

“Then you don’t need to watch any more,” he deadpans.

The Kore-eda starter pack: Not sure where to begin? The director recommends (1) Nobody Knows, (2) Still Walking, and (3) Shoplifters. (Photos: Lighthouse Pictures, Cinequanon, Clover Films)

Look Back (PG) is now in cinemas.

Main photo: Singapore International Film Festival, Purple Plan/Golden Village