Despite returning victorious from a dangerous struggle, Kanata and his friends have, in a sense, lost a key ally, the amnesiac magus Noir. Having partially recovered her memory, Noir reverted back to her former personality: that of Mystere, who acts in a patronizing manner toward her master Kanata. However, Mystere remembers detecting a signal from Histoire, a mystical city, during her former life as an artificially intelligent magus. Meanwhile, Tokio disappears from Rock Town while hunting down the ghosts of his past; however, shocking revelations await the deeper his search goes. As Kanata, his childhood friend Ellie, and the magus diva Ciel set out for Histoire, a hostile organization named Ideal sends assassins after them. If Kanata wants to stand a chance at accomplishing his dream, he must uncover the unpleasant truth about Ideal—and some of his closest allies. [Written by MAL Rewrite]

Following the success of Shiny Colors' first concert, Mano Sakuragi and her friends continue to face new challenges. After Straylight, a new unit of 283 Production, makes its debut concert, the members of the units are temporarily shuffled into new groups to prepare for a Halloween event to help them grow individually as idols. While Mano struggles to express her ideas, her fellow unit member Hiori Kazano feels left out by her new comrades' talent. At the same time, Fuyuko Mayuzumi, who has bitterly failed to become Straylight's center, proves completely unable to show her real personality, jeopardizing the entire project in the process. Shiny Colors' producer will have to find a way for Fuyuko to break out of her shell if he wants to see his idol units illuminate the world once more. [Written by MAL Rewrite]