Ai decides to disappear in order to free Sana. Alina is infuriated by the destruction of Endless Solitude and goes into full attack mode against Iroha and her friends. They find out that the Magius have been using the Uwasa's territory to confine and raise Witches. Iroha and company fight an uphill battle, but Mami and Mifuyu appear on the scene to put an end to Alina’s rampage.

Iroha refuses to join the Magius. When she and Yachiyo meet up, she is eager to go search for Tsuruno and the other girls. However, Yachiyo believes that her wish brings tragedy to those around her and tells Iroha that she is disbanding the team. The Memory Museum begins to collapse. Iroha and Yachiyo try to escape, but Mami, who has become an entirely different person, attacks them.

Yachiyo and Kuroe find Iroha inside the Labyrinth of the Uwasa of the Eternal Sakura. However, Yachiyo and Kuroe are swallowed by the Doppel of Silence that suddenly appears from Iroha’s body. When Yachiyo awakens, she finds herself at Mikazuki Villa eating breakfast with Tsuruno, Felicia, Sana, and Iroha, but Kuroe, who is not supposed to be there, is in the room with them. Yachiyo and Kuroe are baffled by the situation they are in, but they have a hunch that they are not in the real world, but in a dream world being shown to them by the Doppel of Silence. They are concerned about Iroha’s safety in the real world, so they do all they can to wake up Iroha in the dream.

Iroha hears about Nemu Hiiragi, the best friend of Iroha’s younger sister, Ui, from Kuroe. Iroha finds out that Nemu, who is also a member of the Magius, remembers her and asks Kuroe to take her to Nemu so they can talk. Iroha, Yachiyo, and Kuroe head to Hotel Fendt Hope, the headquarters of the Magius. When the trio arrive at Hotel Fendt Hope, they have an encounter with the Amane sisters. While Yachiyo distracts the Amane sisters, Iroha and Kuroe make their way into Hotel Fendt Hope to find Nemu, but they bump into Rena Minami and Kaede Akino, who are dressed as the Black Feathers.

It happened in the past… Iroha would go to the hospital daily and play with Ui, Touka and Nemu. The girls loved Iroha and looked forward to her visits. One day, the three girls create an Uwasa similar to an urban legend while playing. That way, if they died, the Uwasa they created would live on and remind Iroha of them. Iroha also created the “Uwasa of Eternal Sakura”, with the wish that the three girls will be discharged from the hospital without illness. And one day... Kyubey appears before Iroha.

The Magical Girls rush to Iroha while fighting against Uwasa of the Soldier Bear. The Amane sisters also stand in their way, but Mifuyu keeps them in check. "The plans of the Magius have failed." Meanwhile, Iroha and Touka regain the memories that Nemu's power took from them. Touka is happy to be reunited with Iroha but can’t recall why they became enemies in the first place. Nemu tells Touka why she had been hiding the truth until now. Now, they see the promise they made with Ui in a new light.

To fulfill their promise to Ui, Touka and Nemu set their plan in motion with Embryo Eve. Yachiyo desperately tries to stop them. As Alina watches events unfold, Kuroe is isolated and alone. And Kyubey is not far behind… Meanwhile, Iroha wakes up in her room at home. Everything looks the same as when Ui was still around. Finally, Iroha is reunited with Ui.