As a child, Arisu Yamabuki found solace in the voice of a late-night radio host known only as Apollo. Her broadcasts were a comforting presence during a lonely time in his life until she suddenly vanished from the airwaves without any explanation. Years later, Arisu has grown into a driven high school sophomore who has never forgotten Apollo. His search for her, driven by a personal mission to find her and take back an embarrassing confession he once made on her show, leads him to a single clue: a connection to his current school's broadcasting club.

The story is set at Furin High School, where Arisu discovers that the broadcasting club is home to four ambitious girls, each dreaming of a future in voice-based professions. There is Rikka Inohana, the cool and talented club president who aspires to be a singer; Shinobu Uzuki, the kind and responsible vice-president who aims to become a professional announcer; Nene Himekawa, a lively and outspoken girl with dreams of being a voice actress; and Iko Kirino, a shy but creative technical whiz who performs as a VTuber. Each girl possesses a voice that sounds similar to the Apollo he remembers, making it impossible to identify the mystery broadcaster immediately.

Convinced that Apollo must be one of the four, Arisu vows to help each of them achieve their dreams in order to get closer to the truth. A notable narrative arc involves Arisu leveraging his family's wealth and his own perfectionist drive not as a simple handout, but as a catalyst to push the girls to improve their craft, whether through professional-grade equipment or rigorous training. This arrangement creates a complex dynamic where genuine personal connections begin to form amidst the initial transaction. As the season progresses, the series dedicates focused storylines to each heroine, exploring Nene's struggles with script-reading, Iko's battles with performance anxiety, Shinobu's journey to find her authentic on-air voice, and Rikka's hidden insecurities about performing original songs. Throughout these arcs, the question of Apollo's true identity remains a central mystery, with all four girls emerging as equally plausible candidates. The series culminates in a cultural festival performance that brings each character's growth into focus, while the search for Apollo ultimately reveals that the answer is less about unmasking a single person and more about the connections forged in the pursuit.