Arisu Tachibana, a mature grade school student aspiring to be an idol, gets a surprise invitation from her company president to join the Third Entertainment Section, a new idol project. Alongside eight other girls, they meet their unconventional producer, a childlike adult contrary to their expectations. Despite initial disappointments and misunderstandings, the producer, new to the role, is determined to support the young idols with his genuine passion. As Arisu contemplates a producer change, his unwavering dedication to their success wins them over, marking the beginning of a journey towards their dream stage.