Otonokizaka Academy is announced to be closing down after everyone graduates due to lack of applicants, much to the shock of second year student Honoka Kousaka, who loves the school. As she and her classmates Umi Sonoda and Kotori Minami try to think of a way to make the school more attractive to prospective students, Honoka is surprised that her younger sister Yukiho wants to go to a different school, UTX, instead of Otonokizaka. As Honoka decides to investigate UTX, she finds it attracts a lot of students due a school idol group known as A-Rise. Honoka decides that the best way to save her school is to start an idol group themselves, though Umi isn't keen on the idea. As Honoka becomes downhearted, she spots a talented singer and pianist and redoubles her efforts, whilst Umi inevitably gives in and joins Kotori in partaking in Honoka's idea. Despite their request to start an idol club being rejected by the student council president, Eli Ayase, Honoka remains determined to make it work.