Ron Howard is bringing the incredible true story of the 2018 cave rescue of a group of young soccer players to the screen with his latest project, “Thirteen Lives”.

“Like a lot of people, I was aware of what was going on,” he says of what became a global event as the world watched the rescue of 12 young Thai soccer players and their assistant coach from deep within a flooded cave in Northern Thailand. “The outcome was a relief to the world, it was one of those tremendous moments. When I had a chance to read William Nicholson’s script, it not only delivered on what I recalled, but it suggested so much more — the heroics of the people involved, especially the Thai people.”

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“I felt like I could make something really visceral and immediate, the scripted version of what the telling of the true story is supposed to do and make it more engaging,” he tells ET Canada during a Q&A with the cast. With large portions of the dialogue spoken in Thai, Howard says it “was a really exciting, creative opportunity for me and I knew I would also learn about Thai culture.”

For his story, Howard enlisted Colin Farrell, Viggo Mortensen, and Joel Edgerton to portray the real-life divers who helped guide a team of international and Thai volunteers and Thai Navy SEALs in the harrowing rescue mission. In addition to the Hollywood stars as the British and Australian divers, the cast is made up of predominantly Thai actors, including 12 young, non-professional child actors from Northern Thailand to play the trapped soccer team.

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Howard put his entire cast through the ringer while filming in caves and immersed in water on the Australian film shoot.

“They say, don’t work with children or animals, so I’ll throw water into that mix as well,” Farrell who plays diver John Volanthen, says, admitting, “I can’t really swim…. The technical aspect of it really was quite nerve-racking.”

Both Howard and his cast stress how “Thirteen Lives” isn’t the story of foreign heroes.

“It wasn’t about us coming in as actors playing these British divers who were there to save the day and rescue, it was really about us being led by our Thai brothers and sisters and the real divers we were playing,” Farrell explains. “For me, I’ve done various things throughout my career but to be part of something that ultimately at its core, where the world seems to be living under greater and greater division was really about different people from different people, from different cultural backgrounds and nationalities coming together for a common and one that was so terrifying, it was a great gift. We felt that spirit of collaboration.

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“Honestly, it was a joy apart from how nervous I was being in the water every day,” he adds.

Their real-life diving counterparts were heavily involved in the making of the film, which Howard likens to having astronauts on the set of his “Apollo 13”. With Mortensen leading the charge, the cast decided that they wanted to do all the underwater stunts themselves with the guidance of the real-life cave divers.

“There were several moments for all of us where you went, Oh, wow what have I gotten myself into?Mortensen recalls. “There’s a lot of places that were so narrow you just had to wiggle through. Even though it’s a movie, you’re in this place and no one can get to quickly,” he says of having a moment of nervousness on set. The actor ended up having an issue with his tank, but remembered the real [diver Rick] Stanton’s advice and breathe calmly.

(L to R) Thira ‘Aum’ Chutikul as Commander Kiet, Popetorn ‘Two’ Soonthornyanaku as Dr Karn, Joel Edgerton as Harry Harris, Colin Farrell as John Volanthen and Viggo Mortenson as Rick Stanton in THIRTEEN LIVES. Vince Valitutti / Metro Goldwyn Mayer Pictures
(L to R) Thira ‘Aum’ Chutikul as Commander Kiet, Popetorn ‘Two’ Soonthornyanaku as Dr Karn, Joel Edgerton as Harry Harris, Colin Farrell as John Volanthen and Viggo Mortenson as Rick Stanton in THIRTEEN LIVES. Vince Valitutti / Metro Goldwyn Mayer Pictures

“I really had this moment where I started to breathe fast and there was nothing,” he says before remembering the advice the diver had given him. Edgerton, too, had some intense underwater moments during production.

“I did have one moment where I was feeling overwhelmed…. I found it overwhelming and it really hit me how vital it is for everyone to be putting their safety first and to understand how rational and calm the attitude or psyche of regular cave divers would have to be that sets us apart from us regular folk,” Edgerton explains.

Despite garnering headlines and attention from around the world, the stars promise that no matter how much viewers think they know about the real-life rescue, there is so much more to discover in the film.

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“I thought I knew a lot about the story, and then once I got involved in the project there were things that were not really available to the public [at the time], there were elements to the rescue that were really surprising and shocking to people,” Edgerton, who stars as Aussie diver Dr. Harry Harris, says. “It’s rare that I have been that humbled and impressed and nervous about taking on the role because he’s a real national hero in Australia.”

Edgerton says he found the role “incredibly emotional” as he became a first-time father to twin boys during filming.

“It just became even more of a responsibility and the care of children, to me, that felt like such a beating heart of Harry and this story,” he says.

“It was a real dream come true,” adds co-star Tom Bateman. “When I read the script I knew about it, like everything, but I think I knew one per cent of what I know now. What blew me away was the detail of every single person involved and how generous of how the divers were of their time [in preparing for the role]. What we went through was pretty intense.”

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Thai actor Two Popetorn says the film “has been a great experience for all of us Thai actors. The honour to be able to tell our story through Ron’s films, we have the responsibility to tell a really good story for all Thai people.”

For Howard, he “knew that getting really granular, personal, emotional, that this could be an extreme version of my favourite kinds of films that provide that remarkable outcomes are not the stuff of fiction. That when people pull together, incredible things can happen. It’s all driven by my curiosity, to be honest… I love to learn and share what it is,” the director says.

“Thirteen Lives” arrives in select theatres on July 29 and on Prime Video on August 5.

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