Infinity Castle Movie Was in Production Even Before Swordsmith Village Arc Aired

A new pamphlet released alongside the Demon Slayer: Kimetsu no Yaiba – The Movie: Infinity Castle, which included behind-the-scenes details about the movie’s production, has revealed that the first part of the final arc’s trilogy was in production long before the Swordsmith Village Arc even premiered.

The pamphlet, which became available with the film’s Japanese release on July 18, reportedly revealed that the first installment of the Infinity Castle trilogy had a production period of three and a half years. This timeline places the start of production sometime in early 2022, which means the staff at the studio Ufotable were working on the movie while the Entertainment District Arc was still airing. The pamphlet also confirmed that the decision to adapt the Infinity Castle Arc into a movie trilogy was made during the theatrical run of Demon Slayer -Kimetsu no Yaiba- The Movie: Mugen Train, indicating the finale has been in the works, including the planning stages, for nearly five years.

Related

‘Pretty Much Rock Bottom’: Demon Slayer Star Opens Up About Transforming Most Painful Experience Into Positive Outcome

The voice of Tanjiro in Demon Slayer opens up about his most painful experience — and how he uses it to make his voice acting even more phenomenal.

Demon Slayer: Infinity Castle Movie Would Have Taken Longer to Release

Image via Ufotable

According to initial projections, the production of the Infinity Castle movies would have taken significantly longer to complete. Per Magmix, the pamphlet detailed the immense difficulty of recreating the Infinity Castle itself, which shifts in every direction, coupled with characters who engage in some iconic fights in the arc. The initial estimate suggested that the 3DGC rendering process alone would take approximately three-and-a-half years per film, or over a decade for the full trilogy — a schedule the studio deemed “not too realistic.” To meet the deadline, Ufotable expanded its studio with expensive, high-speed machinery and adopted an “all hands on deck” approach after staff warned they wouldn’t finish in time. This ensured the movie was completed without sacrificing quality, making it feasible to release the film just over a year after the anime adaptation of the “Hashira Training Arc” aired.

The overlapping production schedule is supported by the consistency of the anime’s core creative team. Key staff, including director Haruo Sotozaki, Chief Animation Director Akira Matsushima (who is also the character designer) and other ADs, are credited across all installments from Mugen Train to the new Infinity Castle movie. This suggests that the main team has been working on multiple parts of the Demon Slayer story for several years, with a high likelihood that their work on different seasons often overlapped, given the timeline. The pamphlet, however, pointed out that the studio’s workflow involved assigning main animators, including Masayuki Kunihiro, Nozomu Abe, and others, each with their own team to handle action from different perspectives, which helped manage the project’s deadlines.

Related

Demon Slayer Reaches Over 200 Million Copies – But Is Still Only 7th Most Popular Manga Worldwide

Demon Slayer: Kimetsu no Yaiba fans have big reasons to celebrate as the original manga officially becomes the seventh best-selling of all time.

Ufotable’s immense effort has clearly paid off, with the movie earning rave reviews from Japanese audiences and set for a massive box office success, rivaling Mugen Train. When tickets for the early premiere of the movie went on sale on July 14, they sold out almost instantly, with fans reporting website crashes due to high demand. On top of that, major theaters like TOHO Cinemas Shinjuku scheduled as many as 40 screenings of the movie on its opening day alone to commemorate the massive crowds, with fans lining up early in the morning to see the film and purchase exclusive merchandise.

Demon Slayer: Infinity Castle is scheduled to release in the United States on Sept. 12, 2025.

Source: X, Magmix

_{Images are for reference only.Images and contents gathered automatic from google or 3rd party sources.All rights on the images and contents are with their legal original owners.}