Chris Hemsworth talks to his father, Craig, about a cherished photograph in National Geographic's documentary, "A Road Trip to Remember."
Chris Hemsworth and his father, Craig, open up around a camp fire during "A Road Trip to Remember."
In his most personal film yet, Chris turns the camera on his own family after his dad’s recent Alzheimer’s diagnosis. They go together on a road trip into their past, exploring the science of social connection and how it can support memory function. They revisit meaningful places and faces, capturing it all as a home movie, and reviving treasured recollections. (credit: National Geographic/Craig Parry)

National Geographic's new documentary, "Chris Hemsworth: A Road Trip to Remember," opens with the "Thor" actor reflecting on a cherished childhood photo with his father in the Australian Outback.

In the image, Hemsworth's dad, Craig Hemsworth, stares at his golden-haired child with adoration and pride.

"That tells me that that little boy is the only thing that exists in that moment," Chris Hemsworth says in the documentary premiering on Nov. 23 (9 ET/PT and streaming the following day on Disney+ and Hulu). And now it's the actor's turn to give his father the same kind of loving, undivided attention. Craig has "early-stage Alzheimer's, and there’s definitely good days and bad days," Chris says. The duo embarked on a cross-country Australian road trip on motorbikes – making stops in their former homes of Melbourne and the Northern Territory − with hopes of strengthening Craig’s memory.

"We know that revisiting past experiences by talking to someone about it," Dr. Suraj Samtani says in the film, "even using objects from the past or places from the past is a great way to boost our cognition." Samtani says revisiting memories can do for your mind what lifting muscles does for your brain.

Chris Hemsworth gives an update on his health: 'I feel like it’s too far off, hopefully'

In "A Road Trip to Remember," Chris reveals how much he worries about his own health, since discovering during a 2022 episode of his docuseries "Limitless" that he is genetically predisposed to Alzheimer's.

"This has become a very prominent conversation in my world, because I also have two copies of the gene that puts me in a higher-risk category for Alzheimer's," he says in the doc. "But it's not a problem at this point, and it may never be. So I'm far more focused on my dad right now."

The star shares his intention to live in the moment with his mom, Leonie. "I feel like it’s too far off, hopefully," he says. "I'd rather just continue on with life."

Chris Hemsworth's childhood home is replicated with great detail

The house in Melbourne, where Chris lived as a teenager, was overhauled by a dedicated art team to mirror how it looked in the '90s. There's an answering machine, vintage computer relying on dial-up internet and preserved VHS tapes which captured a younger Chris as a crocodile hunter in leg-baring khaki shorts.

Chris and his dad are shocked by the jolt back in time. Craig repeatedly asks when Leonie will arrive, which concerns his son. "I think I'm struggling with wondering, 'Is this going to get better?'" he says.

Leonie also wonders what the future will bring. "As a partner, it’s difficult because I want him to still be the person he was, and I want the relationship−" she says, before getting choked up. "I want that relationship. Sometimes I wake up in the middle of the night, and it can be quite terrifying to think where it's all going."

Craig admits it felt "strange" being in his former home redecorated for the exercise. At the same time, he says, "It's very satisfying recognizing stuff that I hadn’t thought about for a long while."

Those who aren’t working with a film budget can still reap the benefits of this reminiscence therapy, Samtani says. "It can be as simple as listening to old songs together, looking at old photos together or playing home movies and enjoying them together."

This article originally appeared on USA TODAY: Chris Hemsworth gives update on health in moving doc about dad's Alzheimer's

Reporting by Erin Jensen, USA TODAY / USA TODAY

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