Crunchyroll’s Demon Slayer: Infinity Castle continues breaking box office records, and will compete for the animated feature prize at Sunday’s Golden Globes. It’s not only the highest-grossing Japanese film of all time with $682 million worldwide, but also the number one international film ever in North America with $134.5 million.

The decision by animation studio/producer ufotable to turn the “Infinity Castle” storyline into a theatrical trilogy, with its own dramatic arc, has proven wildly successful. This marks a significant leap forward in adapting the popular anime series to the big screen. The first film follows the Demon Slayer Corps in their climactic battle against villainous Muzan Kibutsuji and the Upper Moons inside his Infinity Castle lair with great action and spectacle.

“It’s a very rich story with a lot of elements and material, but, at our studio, ufotable, we don’t like to make the distinction between movies and TV in terms of the quality benchmark,” said studio founder/ creative head Hikaru Kondo via a translator. “We try to look at each project, each anime, each medium and choose the best output and visual expression to match. When we were making Infinity Castle, we thought that if we showed this on a large screen, the audience would be very happy with it. That’s why we chose a movie as the best way for an audience to see it on the big screen.”

But translating that into a feature-length animated film with greater scope (blending 2D and 3D under the direction of Haruo Sotozaki) required special preparation and attention for the three big fight sequences. They focus on key Hashira and Demon confrontations with different choreography, environments, and difficulty: Shinobu vs. Douma, Zenitsu vs. Kaigaku, and the emotional one involving Akaza vs. Giyu & Tanjiro.

“I studied a lot of entertainment, but I couldn’t find any sequels to movies that had three separate battles,” added Kondo. “While writing the screenplay and working on the storyboards, I thought, are we even going to be able to turn this into a movie? Honestly, that was a really big fear thatI had in that early process of pre-production. But somehow we needed to find a way to make all of this come together.”

Kondo pointed to Japanese screenwriter, Shinobu Hashimoto, a frequent collaborator with legendary director Akira Kurosawa (Seven Samurai, The Hidden Fortress), and how they were forced to abandon The Tale of the Eight Samuraibecause storyboarding the battles was too complicated. They streamlined it into Seven Samurai. “But that still didn’t deter me from the original idea, which is I want to see the Infinity Castle in movie theaters on the big screen,” he added. “Somehow, we needed to find a way to make all of this come together.”

It all started with the idea of the Infinity Castle being visually infinite with the various elements moving in a way that defies gravity. “So looking at that lore and setting,” Kondo said, “I thought: how can we take advantage of it? How can we begin to think about the character match-ups, the drama, the situation we can come up with those constraints? There are very few people who can actually create action scenes, so we created a team and made a system where each person would look at the entire scene.

“If normally we would assign 50 shots to you,” he continued, “we’re now going to assign 100 shots. Or we’ll give you 150 shots instead of 100. But, at the same time, we’re going to give you some junior animators as a team. So we gave it up to these masters of action animation and spread the wealth that these grandmasters have. And this lead to the final visual expression that we see on screen.”

Looking back, Kondo considered the first Infinity Castle film the culmination of everything ufotable has accomplished up to this point, and that the transfer of knowledge and skill will allow them to level up in the next two parts of the trilogy and beyond with more series and theatrical movies.

At the same time, Kondo acknowledged that 2025 was a breakthrough year for anime in terms of taking the world by storm and transcending the genre with greater universal appeal and spectacle. This was a long time coming. “Because, in my generation, whenever we would make something international, distributors would come back to us and say, ‘This isn’t Akira, this isn’t Studio Ghibli, this isn’t Ghost in the Shell, so it’s not going to work internationally.’ We just got the door. But this success of anime places it into something larger, which is really great.”