Following the events of Senki Zesshou Symphogear G, Hibiki Tachibana, Tsubasa Kazanari, and Chris Yukine continue to operate under the command of Genjuurou Kazanari. Meanwhile, Maria Cadenzavna Eve, Kirika Akatsuki, and Shirabe Tsukuyomi are taken into protective custody. With peace restored, everyone returns to their daily lives; however, the appearance of the alchemist Carol Malus Dienheim and her subordinates—the "Autoscorers"—threatens to draw everyone back into a conflict. Armed with a strange and magical power, Carol wishes to initiate the apocalypse and bring destruction to the world... and she is willing to sacrifice everything to do so. Against this mysterious new foe, the six Symphogear wielders must rise to the challenge in order to protect what they hold dear. However, will Carol and her Autoscorers prove to be too much to handle in this fight to protect the fate of the world? [Written by MAL Rewrite]

Hibiki Tachibana has defeated many powerful enemies, saved countless innocent lives, and escaped from numerous desperate situations, but she is currently finding herself unable to escape from her most desperate situation yet—summer homework! Although her high school life is relatively unremarkable, her career as a member of the military organization S.O.N.G. is anything but. Using powerful, ancient armor known as Symphogear, Hibiki and her teammates work with the United Nations to deal with international disputes and disasters. During a mission briefing at headquarters, Hibiki is made aware of a mysterious organization known as the Bavarian Illuminati, who has been responsible for several major disasters in the past and currently operate in the war-torn country Val Verde. Together, Hibiki and her team infiltrate one of the Bavarian Illuminati's manufacturing plants and free hundreds of slaves. Exposed, alchemists Saint-Germain, Cagliostro, and Prelati reveal themselves as the organization's top brass, and—using alchemical powers—declare a global revolution while sacrificing thousands of lives. Faced with yet another threat to the world's survival, Hibiki and her allies must confront the Bavarian Illuminati in their most difficult and destructive battle yet. [Written by MAL Rewrite]

Humanity is finally confronted with the threat of the Custodians—the ancient, sentient species held responsible for cursing humanity to speak different languages thousands of years ago. The Symphogear wielders—Hibiki Tachibana, Tsubasa Kazanari, Chris Yukine, Maria Cadenzavna Eve, Kirika Akatsuki, and Shirabe Tsukuyomi—are sent to the Antarctic in order to retrieve an ancient relic. After securing it and rescuing the scientific staff present there from a Coffin, the automated defense mechanism protecting it, the relic is given to American researchers due to international agreements. The criminal organization Noble Red, a remnant of the previously fought Bavarian Illuminati, starts targeting the relic. Will the Symphogear wielders and their supporting organization S.O.N.G. be able to foil the plans of the organizations conspiring against them? [Written by MAL Rewrite]

Six years ago at the magic school known as the Tower of Fang, a grave accident happened involving the magical sword Baltanders and the magic user Azali. Unable to control the sword's power, Azali was transformed into the shape of a great dragon who since that day became known as Bloody August. Krilancelo, a young magician at the Tower who cared greatly for Azali found much to his disgust that the elders of the Tower of Fang were less than willing to save Azali and wanted rather to pretend the accident never happened. Angered by their stand, Krilanceloa swore that he would find a way to return Azali to her former self. Thus he forsook the name Krilancelo and declared himself Orphen, leaving the Tower and his magical studies behind to wander the world... (Source: ANN)