Mari Ohara, a third year student and newly assigned as the director of Uranohoshi Girls' Academy, states that if the girls can fill up the school gym with audience members, she will approve their School Idol Club. Realising that there aren't enough students in their school to fill the gym, the girls are forced to search outside the school to advertise their concert. While trying to come up with a name for their group, the girls stumble upon the name "Aqours" anonymously written on the beach and decide to use it. On the day of the concert, only a handful of students show up, but the girls perform their hearts out nonetheless. Just as a power outage occurs and all hope seems lost, a whole crowd of people, who heard about the concert through Chika's sister and friends, arrive at the gym, while Dia secretly hooks up a backup generator, allowing the concert to continue.