An Epic Production Filmed Across Thailand – Conquering More Than 3,000 Hairpin Turns to Capture the Perfect Shot

Interview compiled by Benjarong Kotchanawong

Get ready for a heart-pounding survival thriller with The Devil’s Mouth, the story of five young adventurers who embark on a journey along Thailand’s breathtaking coastline. Their expedition leads them to a remote cave known as “The Devil’s Mouth,” where they join a cave-diving tour, only to discover that something is stalking them beneath the water. Swift. Silent. Deadly.

The film was shot across several stunning locations throughout Thailand, including Bangkok, Krabi, Mae Hong Son, and Samut Prakan.

The cast features a talented lineup of rising stars, including Kathryn Newton, Lana Condor, Gavin Casalegno, Nico Hiraga, and Tommi Rose, alongside internationally recognized Thai actor Tayme Thapthimthong. The Devil’s Mouth is now streaming on Prime Video.

Today, we bring you an exclusive interview with the film’s cast and director.

Exclusive Interview: Tayme Thapthimthong

What was your first reaction after reading the script and joining The Devil’s Mouth?

First of all, I felt incredibly proud to be part of this film because it was shot entirely in Thailand, both in the north and the south of the country. It’s a wonderful opportunity to showcase the beauty of Thailand to audiences around the world.

In the film, I play a tour guide who leads foreign tourists into an underwater cave. I was especially excited when I learned there would be numerous underwater scenes, so I actually looked forward to the diving training long before filming even began.

Tell us about your role as the tour guide.

I play a cave-diving guide who takes a group of international tourists into a cave called “The Devil’s Mouth.”

When I spoke with Jeff, the director, he wanted my performance to feel as natural as possible. My character is a local guide who knows the cave inside and out. At first, he doesn’t suspect that anything is wrong. But once disaster strikes, his only goal becomes getting every member of the group out alive.

It wasn’t a particularly difficult role because authenticity and realism were the most important aspects of the character.

The film involves cave exploration, climbing, and extensive underwater sequences. How did you prepare physically before filming?

About a month before principal photography began, all six main cast members attended a workshop together in a two-meter-deep swimming pool.

Professional diving instructors trained us in freediving—holding our breath while diving without oxygen tanks—as well as the basics of scuba diving.

We trained in the pool almost every day for nearly a month. We also practiced breath-holding because many of the scenes required us to stay underwater for extended periods during filming.

Fortunately, I’ve always enjoyed swimming, so the training wasn’t too difficult for me. It was a fun experience, and it also helped all of us become much closer before production officially started.

Was there a particular scene that was especially challenging or memorable?

One of the first locations we filmed at was a cave entrance in Mae Hong Son, where we shot a canoe sequence. After that, we moved to a cave in Krabi.

Everyone was excited because we had to film in real water. The cave water was cold, murky, and filled with branches and leaves. Fortunately, professional divers always inspected the area beforehand to ensure everything was safe.

There was one scene where the tourists had to jump into water that was about 30 meters deep. Naturally, everyone was a little nervous.

At one point, I had to float alone in the middle of the water while waiting for the next take. I couldn’t help imagining whether a fish—or something else—might suddenly appear beneath me. (Laughs.) But thankfully, everything was completely safe.

Another cave we filmed in was nearly 70 meters deep and incredibly dark. During one scene, someone accidentally kicked another actor with a diving fin, which startled everyone. Looking back, though, it’s something we can all laugh about now.

After that, we continued filming in a studio in Bangkok. The production design team did an outstanding job building two full-scale cave sets.

One was a five-meter-deep underwater cave specifically designed for underwater scenes, while the other featured water approximately 1.6 meters deep so actors could stand comfortably during dialogue scenes instead of floating the entire time.

The set was designed like a maze, allowing us to swim through interconnected chambers. It was truly impressive.

The film was shot in several provinces across Thailand. Which location was the most challenging?

For me, Mae Hong Son was definitely the most challenging—not because of the filming itself, but because of the journey to get there.

We had to drive through more than 3,000 winding mountain curves to reach the location.

Many of the international cast members had only just arrived in Thailand. They weren’t yet accustomed to the climate or the long, winding mountain roads, so the crew asked me to help take care of them.

I ended up becoming a real-life tour guide as well. I handed out motion sickness medicine, asked the driver to stop whenever someone needed a restroom break, and helped everyone get through the trip as comfortably as possible. Sometimes stopping wasn’t even possible because it would block the narrow mountain road for the vehicles following behind us.

Some of the cast members felt carsick, while others desperately needed a restroom. Looking back now, it was quite a chaotic experience—but also a funny one.

It wasn’t just the cast making the journey. Every department—from the makeup team and equipment trucks to the crane operators—had to travel the same mountain route.

On top of that, we had to wake up at 4:00 a.m. every day to make sure we were ready to capture the first light of sunrise.

What was it like working with the international cast in Thailand?

Everyone absolutely loved Thailand.

While we were filming in Krabi, we stayed at a beachfront hotel with a swimming pool, and all of us were staying close to one another. It created a warm, relaxed atmosphere that made working together even more enjoyable.

We would have dinner together, go swimming, enjoy cocktails, and watch the sunset after filming.

I felt proud to introduce them to experiences they had never had before because, for many of them, it was their first visit to Thailand.

I took them to local restaurants in Ao Nang, introduced them to authentic Thai cuisine, and showed them how local people live so they could experience more than just the hotel.

Those moments remain some of my favorite memories from the entire production.

What was it like working with director Jeff Wadlow?

Working with Jeff was an incredible experience.

He’s an exceptionally talented director, easy to talk to, and a genuinely fun person to work with.

I’d been a fan of his films for years, especially Kick-Ass 2 and Never Back Down, which I loved growing up. So when I found out I’d be working with him, I was thrilled.

Jeff later told me that he had seen my performance in The White Lotus and liked my work, which is why he reached out and offered me the role directly.

This was actually the first acting job I’ve ever received without having to audition.

Knowing that the film would also be shot in Thailand made it an even easier decision to accept, since it gave me the chance to come home and spend time with my family.

Working with Jeff was smooth from beginning to end. He’s straightforward, clear in his direction, and after production wrapped, we’ve remained good friends and still keep in touch regularly.

Exclusive Interview: Lana Condor

How did you feel when you were first offered a role in The Devil’s Mouth?

Honestly, my first thought after reading the script was, “Whoever agrees to star in this movie has to be completely crazy.” Then, almost immediately, I thought, “Well, I must be just as crazy if I turn it down.”

The script was simply that good.

One of the things that excited me the most was the opportunity to film in Thailand. I’d wanted to visit Thailand for a very long time, so that was one of the biggest reasons I decided to join the project.

Another reason was that I was looking for a role that would truly challenge me as an actress. I absolutely love romantic comedies and have enjoyed working in that genre, but I also wanted to see how far I could push myself by taking on something completely different.

The chance to collaborate with Jeff, the producers, the cast, and to work with such a strong script made the decision even easier.

This film demanded a great deal physically. How did you prepare for such an intense role?

Without a doubt, this was an incredibly demanding film from a physical standpoint.

One thing I rediscovered while returning to a more action-oriented project is that I genuinely enjoy roles that push me to my physical limits.

When my body is under real stress and pressure, my performance naturally becomes more authentic. It becomes easier to believe in the situation my character is experiencing, and I think that authenticity helps the audience believe in it as well.

That said, this film was unlike anything I’d done before.

Most of my previous action projects revolved around fight choreography, but The Devil’s Mouth isn’t about fighting—it’s about survival.

The challenge wasn’t defeating an enemy; it was simply staying alive.

Even while the crew was resetting cameras or preparing for the next take, we couldn’t just relax. We had to keep swimming or tread water continuously so we wouldn’t sink.

Because of that, this film delivers action through survival rather than combat. Every moment demands physical endurance, making it a very different kind of action thriller.

Much of the film takes place underwater. What was the most difficult aspect of filming those scenes?

The biggest challenge was undoubtedly spending so much time in the water.

Filming underwater is already difficult enough, but doing it inside caves made everything even more demanding.

There were times when we had to remain submerged for extended periods, repeatedly performing the same scenes while conserving our energy.

The water was cold, visibility was often poor, and we had to stay focused on both our performances and our safety at the same time.

Fortunately, we had an incredible team of professional divers and safety specialists looking after us throughout the entire production, which gave us the confidence to fully commit to every scene.

What was it like working alongside the rest of the cast?

One of the best parts of making this film was the people.

Everyone was incredibly supportive of one another from day one.

Because we went through diving training together before filming began, we built trust and formed genuine friendships long before the cameras started rolling.

During production, we spent so much time together—in the water, on set, and after work—that we became like a little family.

That bond naturally translated onto the screen and helped make our performances feel much more believable.

What was your experience filming in Thailand like?

I absolutely fell in love with Thailand.

The country is stunningly beautiful, the food is incredible, and the people are some of the warmest and kindest I’ve ever met.

I’d wanted to visit Thailand for years, and finally getting the opportunity through this film exceeded every expectation I had.

It wasn’t just another filming location—it became an unforgettable experience.

I sincerely hope I’ll have the chance to return, whether for another film or simply as a visitor.

Exclusive Interview: Director Jeff Wadlow 

What inspired you to direct The Devil’s Mouth?

I think almost every filmmaker dreams of making a shark movie at least once in their career. I mean, why wouldn’t you? Shark films have become a genre all their own.

That said, audiences today are always looking for something fresh and different, so I knew that if I were going to make a shark movie, it had to offer something unique.

What immediately drew me to The Devil’s Mouth was that, while it’s undeniably a shark film, it’s also a claustrophobic survival horror story. That’s a genre I’ve wanted to explore for a long time.

As I continued reading the script, I became even more impressed. Every character felt layered and complex, especially the relationships between the female characters, which form the emotional heart of the story. Their dynamic was written with remarkable depth and nuance.

I was hooked almost immediately and didn’t hesitate to say yes.

The film was shot in several locations across Thailand. Why was Thailand the perfect place for this story, and what was your experience like filming here?

Filming in Thailand was an absolutely incredible experience.

I genuinely fell in love with the country. It was one of those once-in-a-lifetime adventures that every filmmaker hopes to have.

In fact, after production wrapped, I came back to Thailand just to visit the friends I had made while working here. I’m already looking forward to returning to shoot another film in the future.

The Thai crew was exceptional, and every filming location was breathtakingly beautiful.

Honestly, I could spend hours talking about all the reasons why Thailand is such an amazing place to make movies.

If you asked me to choose my favorite location in Thailand, I honestly couldn’t. It wouldn’t be fair.

Every place we visited had its own unique beauty and character, and every location was incredibly cinematic.

All I can really say is that my entire experience in Thailand was extraordinary.

Did you have the chance to try Thai food? Was there a particular dish you enjoyed the most?

There’s actually a funny story behind that.

I’m severely allergic to peanuts.

Originally, the script was written with Mexico as the filming location. When the studio suggested moving production to Thailand, my first reaction was, “That might not be such a great idea.”

To be honest, I’d never even dared to eat at a Thai restaurant before because I was always worried about accidentally eating peanuts.

But the Thai production team reassured me.

They told me, “Don’t worry. We’ll take good care of you. Everything will be fine.”

And they were absolutely right.

I had an amazing time, and Thai food turned out to be absolutely delicious.

Avoiding peanuts wasn’t nearly as difficult as I’d imagined. I simply learned to stay away from dishes like Massaman curry and Pad Thai.

That said, I definitely found a favorite.

Pad Kra Pao became my go-to dish. I could honestly eat it every single day and never get tired of it.

Another unforgettable experience was traveling around northern Thailand near Chiang Mai and exploring Krabi in the south while scouting filming locations.

Along the way, we stopped at countless small roadside restaurants.

Every meal was flavorful, authentic, and packed with character, and every restaurant owner welcomed us with incredible warmth and hospitality.

I truly loved every moment I spent in Thailand.

By now, you can probably tell just how much I love this country.

I honestly can’t wait to come back.

The film features numerous underwater sequences. From a technical standpoint, what was the biggest challenge, and was there a particular scene that proved especially difficult?

To be completely honest, this film was difficult from beginning to end.

There wasn’t a single easy day.

Most productions have lighter shooting days that allow the cast and crew to catch their breath, but The Devil’s Mouth wasn’t that kind of movie.

Every single day presented a new challenge.

Almost the entire film takes place in water, and much of it is set inside caves.

We filmed in real caves across Thailand, and we also built enormous cave sets in the studio before filling them with water.

As everyone knows, cameras and water aren’t exactly best friends.

Even shooting near water is challenging, but filming completely underwater requires highly specialized equipment and an extraordinary amount of planning.

There was nothing easy about making this film.

Yet we were fortunate to have two things that carried us through every challenge.

The first was our incredible crew—especially the Thai crew, who never backed down from any obstacle.

They were among the most dedicated, hardworking, and resilient professionals I’ve ever had the privilege of working with.

The second was our phenomenal cast.

Led by Kathryn Newton and Lana Condor, they were always willing to dive in—literally and figuratively.

Together, we tackled every challenge one step at a time and found solutions to every problem we faced.

Tell us a little about the cast. What impressed you most about working with them?

When I’m casting a film, I’m not simply looking for actors who fit the roles. I’m looking for people who are genuinely interesting.

I want actors who can bring something uniquely their own to a character—something that goes beyond what’s written on the page.

Our five lead actors, Kathryn Newton, Lana Condor, Gavin Casalegno, Nico Hiraga, and Tommi Rose, are all incredibly charismatic people in real life.

Each of them brought their own personality, life experience, and perspective to the film, which made every character feel vibrant, authentic, and deeply relatable.

They’re the kind of characters audiences will root for. They’re fun to watch together, but they’re also flawed and imperfect in ways that make them feel genuinely human.

As for Tayme Thapthimthong, who plays our local tour guide, I feel incredibly fortunate that he agreed to join the film.

He had just finished filming The White Lotus Season 3, and I thought he delivered an outstanding performance in that series.

When I found out he was not only available but also genuinely interested in playing this role, it honestly felt like a dream come true.

If you had to describe The Devil’s Mouth in just three words, what would they be?

I’d describe it with these three words:

Thrilling. Emotional. Water.

Those three words capture the spirit of the film perfectly.

Beyond the thrills of a shark movie, is there a message or feeling you hope audiences will take away from The Devil’s Mouth?

At its core, I believe this film is about survival and perseverance.

But another idea stayed with me throughout the entire filmmaking process—the importance of respecting nature.

Nature is breathtakingly beautiful, and that’s precisely what makes it so powerful and awe-inspiring.

At the same time, however, nature can also be incredibly dangerous.

Our role isn’t to conquer nature or believe we can control it.

Our role is to admire it, respect it, and recognize its power.

If we fail to show that respect, the consequences can be devastating—even fatal.

That’s exactly what some of the characters in this story experience.

Throughout their journey, they learn that nature is not something to challenge or take lightly.

It’s something that deserves our humility and respect.

A Final Message to the Audience

The Devil’s Mouth is more than just a shark thriller.

It’s a story about friendship, courage, resilience, and the instinct to survive against overwhelming odds.

Set against the breathtaking landscapes of Thailand, the film combines spectacular natural scenery with relentless suspense, delivering an adventure that’s both visually stunning and emotionally gripping.

Whether you’re drawn in by the underwater action, the survival story, or the unforgettable locations, The Devil’s Mouth promises a cinematic experience unlike any other.

Now streaming exclusively on Prime Video.