Shuhei Yamamoto, Masahiro Motoki, is a busy Kyoritsu University student who lands a job through his uncle’s network, but a setback soon surfaces: the supervisor of his graduation thesis, Professor Tokichi Anayama, Akira Emoto, reveals that Shuhei is short on credits needed to graduate. To keep him in the program, Anayama strikes a deal: if Shuhei participates in the university’s sumo tournament, the missing credits might be overlooked. On the other end, Natsuko Kawamura, Misa Shimizu, a graduate student from the Anayama Lab who also runs the sumo club, pushes for Shuhei’s involvement, and he reluctantly agrees, driven by a mix of obligation and curiosity.
The Sumo Club begins with a slim roster and a stubborn tradition. The club’s only current member is Aoki Tomio, Naoto Takenaka, a devoted classicist who has spent years in the sport. Shuhei and Aoki struggle to recruit teammates, including Shuhei’s younger brother Haruo Yamamoto, Masaaki Takarai, and the larger-than-life, stubbornly overweight Hosaku Tanaka, Fuyuki Murakami. Their first tournament as a makeshift squad ends in a loss, and the post-match party turns hostile as alumni abuse the team, testing their resolve and unity. Yet Shuhei’s stubborn hope never wavers, and he vows that they will come back stronger. To shore up their chances, he invites a new ally: George Smiley, Robert Hoffman, a British student and experienced footballer who joins the ranks to help with rent and bring a fresh perspective to the team.
During the sweltering summer break, the team travels to Anayama’s hometown for a training camp. The intense sessions push the players beyond their limits, and the squad finishes the camp with a local practice match against neighborhood elementary schoolers, a humbling but revealing experience that bonds them and tests their discipline. The early momentum continues as the club secures a critical win in the next third league match, earning a promotion into the second league. However, the road is not smooth: Haruo breaks his arm in the third match, and Shuhei himself sustains injuries that threaten his ability to lead.
In a bid to steady the team’s morale and keep the dream alive, Masako Mamiya, a female manager with a crush on Haruo, volunteers to join as a member. On the day of a crucial match, Masako makes a bold gesture—binding her chest with bandages and tape—but loses, a moment that nonetheless inspires the squad. With renewed vigor, Tanaka and Aoki claim their own victories, and the team rides the wave of momentum as the league’s final rounds approach. The dramatic culmination comes when Shuhei delivers a decisive throw, flinging his opponent out of the ring and sealing a hard-fought league win.
As the season closes, the outcomes begin to shape the futures of the players. Tanaka is scouted for sumo wrestling, Smiley returns to Britain, and Masako and Haruo depart to study abroad in London. Aoki graduates, leaving Shuhei faced with a defining choice: continue the club as its sole remaining member or pursue other opportunities. In a quiet, bittersweet moment, Natsuko visits Shuhei in the club, and the film ends on a gentle note as they practice shiko together, a hopeful sign that passion and friendship can endure beyond the season’s end.
