"Gekijō-ban Argonavis Axia" is a film adaptation of the multimedia project "Argonavis from BanG Dream!" and serves as a continuation of the anime series "Argonavis from BanG Dream! AAside." The story centers on the all-male band Argonavis, which consists of five members: Ren Nanahoshi, Yuto Goryo, Wataru Matoba, Banri Shiroishi, and Rio Kikyo. The band faces internal and external challenges as they strive to achieve their dreams in the competitive world of music.

The narrative begins with Argonavis preparing for their next big performance, but tensions arise within the group due to differing aspirations and creative conflicts. Ren, the vocalist and leader, struggles to balance his passion for music with the pressures of leading the band. Yuto, the guitarist, grapples with his own insecurities about his abilities, while Wataru, the bassist, seeks to find his place within the group. Banri, the drummer, and Rio, the keyboardist, also face personal dilemmas that test their commitment to the band.

As the story progresses, Argonavis encounters a rival band, Gyroaxia, whose intense rivalry pushes them to confront their weaknesses and grow stronger. The rivalry serves as a catalyst for Argonavis to reflect on their unity and purpose as a band. Through a series of emotional and dramatic events, the members of Argonavis learn to overcome their individual struggles and reaffirm their dedication to each other and their music.

The film culminates in a climactic performance where Argonavis delivers a powerful and heartfelt performance, symbolizing their growth as individuals and as a band. The resolution highlights themes of perseverance, friendship, and the transformative power of music, leaving a lasting impression on both the characters and the audience. The story of "Gekijō-ban Argonavis Axia" is a testament to the challenges and triumphs of pursuing one's dreams in the face of adversity.