Traumatized by school, Jun Sakurada spends his days at home as a shut-in, purchasing things online, only to send them back before the free trial period ends. So when a note appears on his desk, asking whether or not he would wind something, he assumes it was something he ordered and carelessly circles yes, changing his life forever. A box arrives with a wind up doll inside, but this is no ordinary toy: after Jun winds her up, she begins walking and talking as if a normal person. With a haughty attitude, she introduces herself as Shinku, the fifth doll in the Rozen Maiden collection, a group of special dolls made by the legendary dollmaker Rozen. These sisters must battle each other in a competition called the Alice Game with the help of a human to ensure victory. The winner becomes Alice, a real girl who is worthy of meeting their creator. As more sentient dolls end up taking residence in Jun's house, and a foe from Shinku's past makes her appearance, Jun's life becomes far more complicated than he ever thought possible.

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.

Tsubasa Kazanari and Kanade Amou—the idol duo known as Zwei Wing—use their songs to power ancient weapons known as symphogears to combat a deadly alien race called the Noise. While the general public is aware of the Noise's existence, knowledge of the symphogears are kept a secret. When the Noise attack one of Zwei Wing's concerts, Kanade sacrifices herself to protect a young girl named Hibiki Tachibana, leaving Tsubasa devastated and a fragment of her symphogear embedded within Hibiki. Two years pass and Hibiki is once again dragged into a Noise attack. While rescuing a young girl who has been left behind during the evacuation, she awakens the power of Kanade's symphogear lying within her. Although Tsubasa still grieves over the loss of Kanade, both girls must now learn to work together using their powers to defend humanity against the Noise.

Three months after a Lunar Attack which nearly caused Earth's destruction, Hibiki Tachibana, Tsubasa Kazanari, and Chris Yukine continue to fight the Noise—a mysterious alien threat—using powerful armor known as Symphogear. After defending an American convoy from a Noise attack, Hibiki and Chris race toward the Queens of Music concert hall to attend one of Tsubasa's concerts. Meanwhile, Tsubasa and rising international superstar Maria Cadenzavna Eve deliver an amazing performance that is broadcast throughout the entire world. Just as the concert is about to conclude, a group of Noise suddenly appear, plunging the hall into chaos. Amidst the panic, Maria declares war against the world as the successor of Finé—Chris' former mistress—and her allies Kirika Akatsuki and Shirabe Tsukuyomi reveal Symphogear powers of their own. After initiating a skirmish with Tsubasa and her teammates, they retreat mysteriously, leaving the three friends bewildered as to what their true intentions could be.