Poppin'Party, Roselia, and RAISE A SUILEN's successful concert at the Budokan has passed. Kasumi and the others, who have left a lingering sound on the stage of their dreams, are approached by a mysterious woman. Their next stage is overseas?! Poppin'Party's music isn't stopping yet!
After overcoming numerous tribulations, the members of Roselia promised to appear on FUTURE WORLD FES. It is now Autumn... Through writing the lyrics of "Promise," Lisa has matured. Watching the change of color in the autumn leaves, Yukina and Sayo expressed their resolve in a picture letter to their future selves. Driven by the wish to do something for Roselia, Rinko has started to compose a new song. "The remaining quests are the contest, the tournament, and FUTURE WORLD FES..." Reflecting on their goals, Ako starts to feel anxious. What view will the five of them see beyond FUTURE WORLD FES?
Yukina Minato gathers members intertwined with different thoughts to form a band and participate at the Future World Fes. This is the story of their "promise" from their formation to the challenge of the music festival.
In the near future, the existence of "Adepts," people who possess extraordinary abilities known as "Septimal Powers," has caused widespread chaos around the world. In the nation of Japan, order and peace is maintained by a large conglomerate known as the Sumeragi Group. One group known as QUILL (Quorum for Unrestricted Information, Law, and Liberty) pledged to revolt against the Sumeragi Group.
Although μ's, the defending champions of the school idol tournament, plans to dissolve their group after the graduation of their senior members, they receive news that leads them to holding a concert event! The 9 girls continue to learn and grow in this new and unfamiliar world. What is the last thing that these girls can do as school idols? With the clock ticking, what kind of meaning will the μ's members find in performing the most exciting live performance?
