The cast and crew behind Demon Slayer: Kimetsu no Yaiba Infinity Castle hit the stage at San Diego Comic-Con, offering fans an exclusive look behind the curtain of the most ambitious arc yet. Director Haruo Sotozaki, Director of Photography Yuichi Terao, and voice actors Natsuki Hanae and Aleks Le gave attendees a deep dive into the creative process, visual challenges, and emotional stakes leading into this grand finale.

From Manga Lines to Moving Frames

Kicking off the panel, Sotozaki revealed how meticulous the process was in translating the manga to the screen. “I paid very close attention to the lines, the thickness of the lines. I wanted to make sure that information was preserved when we adapted the manga to the anime,” he said.

That painstaking attention to detail also extended to the show’s signature elemental techniques. “The water breathing technique, we drew inspiration from ancient Japanese ukiyo-e style artwork,” Sotozaki explained. “We first made the waves using 3D models, but then we had to translate that and add some 2D key frames on top of it to ultimately land on the type of visual expression you see.”

Yuichi Terao broke down his essential role as director of photography, likening himself to a visual assembler. “We get all these different materials from different team members—character animation, the background, the effects—and they’ll all land on my desk. I take all of these different elements and then compile them into a single shot,” he said.

Of course, that pursuit of visual beauty comes with its own hurdles. “We’re going for the most epic and gorgeous anime you can get,” says Terao. “Nevertheless, when you try to make the imagery too gorgeous… some of the original lines that the animators had drawn get kind of blended into the background, and they don’t stand out. And then that’s when Sotozaki-san and [Akira] Matsushima-san, our chief animation director, came to my desk and said, ‘Hey, where did all of our lines go? We can’t see them.’” Sotozaki chimed in with a deadpan response: “Yes.”

A Battle for the Ages

A new key visual featuring Tanjiro and Giyu squaring off against Akaza premiered during the panel, too. Sotozaki shared, “We drew a lot of inspiration from the movie itself to come up with the composition.” As for what that image might be teasing, Tanjiro’s voice actor Natsuki Hanae played coy: “I can’t really tell you what’s gonna happen in the movie, but perhaps that visual gave us a few hints, you know, maybe Tanjiro is gonna go up against Akaza. I know in Mugen Train, Tanjiro couldn’t do anything, so it’s gonna be a spectacle to see how much Tanjiro has grown since the last film.”

Aleks Le, the English voice of Zenitsu, teased an emotional evolution for his character. “He’s very extreme on all ends… but something that we haven’t seen yet is his more vulnerable side, and I feel that this film is gonna bring out a whole new version of him that nobody’s prepared for.”

If this panel was any indication, Demon Slayer: Kimetsu no Yaiba Infinity Castle isn’t just raising the stakes—it’s redefining what anime finales can be.

Demon Slayer: Kimetsu no Yaiba Infinity Castle hits U.S. theaters on September 12th.