Uoto and Kenji Iwaisawa Collaborate on Hyakuemu Film Adaptation
The collaboration brings together two artists who, despite different personalities and methods, share a fascination with humanity's irrational drive, resulting in a film that uses an unorthodox production pipeline to match its thematic content.
Reporting from 1 sources: Sakuga Blog.
Manga artist Uoto, known for "Chi: On the Movements of the Earth," and director Kenji Iwaisawa, acclaimed for "On-Gaku," have teamed up for a theatrical adaptation of Uoto's debut manga "Hyakuemu" (also known as "100 Meters"). The film, released in September 2025 to coincide with the Tokyo World Athletics Championships, follows the stories of 100-meter sprinters, exploring their obsessive dedication to a sport where years of preparation can be undone in fractions of a second. Iwaisawa, who had been a fan of Uoto's work before being approached by producer Yusuke Terada in July 2021, adapted the five-volume manga into a 100-minute film. The production was notable for its unconventional approach: Iwaisawa turned his personal company Rock'n Roll Mountain into a full animation studio after failing to find a traditional pipeline that fit his methods. The film blends rotoscoping, 3D models, and freehand animation, and features a celebrated 3-minute 40-second uninterrupted tracking shot of pre-race preparations that took a year to animate. Character designer Keisuke Kojima played a central role in the production.
The film's production began when Pony Canyon producer Yusuke Terada approached Iwaisawa in July 2021, just weeks after the director had read Uoto's manga and become an enthusiast. The script went through four drafts as the two creators refined the adaptation, with Uoto focusing on small details like line placement while agreeing to Iwaisawa's structural changes, including the removal of many of the manga's lengthy monologues in favor of visual expression.
Iwaisawa assembled a crew that mixed complete newcomers recruited via social media, independent artists who had worked on "On-Gaku," and industry veterans. Character designer Keisuke Kojima was central to bridging these groups, using Clip Studio Paint to create scene roughs that guided key animators. The workflow began with Iwaisawa directing live-action actors in exaggerated performances, then editing the footage to adjust timing before Kojima drew roughly one in ten frames as guidelines for rotoscoping.
The film opens with a stylized sequence by independent artist Ryoji Yamada depicting the history of running, followed by a childhood arc animated entirely without rotoscoping. Iwaisawa explained this choice as representing the detachment of memory. The highlight is a 3-minute 40-second single tracking shot of pre-race preparations that required nearly 10,000 sheets of paper and took a year to animate, with Iwaisawa himself drawing thousands of trees over recorded footage alongside Koshiro Tokoro.
Synthesized by Yomimono from the 1 cited source below, including Japanese-language reporting where cited, then editorially reviewed before publishing.