Iroha decides to investigate Kamiahama City’s rumors in order to find clues about her missing sister, Ui. Mitama introduces Iroha to Tsuruno, the daughter of the owner of a Chinese restaurant called Banbanzai. Tsuruno asks someone who is familiar with the rumors to help investigate, but Yachiyo is the one who shows up at the meeting spot. Tsuruno says Yachiyo is knowledgeable about the rumors of Kamihama City. The three suspect that the Séance Shrine may have something to do with Ui’s disappearance…

Felicia was asked to join the Wings of the Magius, an organization that works within the shadow of rumors. She betrays Iroha and her friends and joins them. Kyoko is also invited by the Wings of the Magius and decides to join the organization. Iroha and company track Felicia down to an underground waterway, where the Wings of the Magius lurk. When the good luck count from the Lucky Owl Water reaches zero, it is said that unimaginably bad luck will befall whoever drank it.

Iroha is convinced that all rumors are connected, so she decides to reply to the spam messages that are being repeatedly sent to her. The one who has been sending the texts calls herself Ai, and she asks Iroha to come to Endless Solitude to delete her existence. However, Sana Futaba, who is a captive in Endless Solitude, seems to be satisfied with her life there.

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.

The Magical Girls break into the headquarters of the Magius. After Iroha and Yachiyo reunite, they meet up with Madoka and the other girls, but are confronted by Tsuruno Yui and Mami Tomoe who have become soldiers of the Magius. Mami and Tsuruno, who are being manipulated by another entity, begin attacking the Magical Girls. Iroha and Madoka are in a bind as they are unable to fight back. As a tactic, the Magius summon countless Witches to gather in Kamihama City. The largest ever Supercell is approaching and will hit Kamihama City in six hours. The true identity of the Supercell is actually Walpurgisnacht, the most sinister and evil Witch ever.

Tsuruno, who had merged with the Uwasa, is defeated, which triggers Touka from the Magius to direct her rage toward Iroha and her friends. Touka sends the Uwasa of the Soldier Bear army to attack them. Nemu is upset with Touka’s actions and at how things aren’t turning out the way she intended. Meanwhile, Iroha finds herself alone in a strange world. She is sitting in a seat in a theater where a Magical Girl named Mel is predicting the future. When Iroha sees Mel, she remembers the past events that Touka showed her at the Memory Museum.