While taking a ferry to Fuuka Academy, new students Mai Tokiha and her sickly younger brother, Takumi, spot a girl adrift on the water. Shortly after bringing her aboard, the ferry comes under attack from an assailant who summons a mechanical monster. Despite still recovering from her injuries, Mikoto Minagi fends off the monster using a supernatural sword. Mai soon discovers that Mikoto is a fellow Fuuka Academy student with abilities called HiME (Highly-advanced Materializing Equipment). Female students with HiME are responsible for defending the academy and the local city from the monstrous Orphans. After several incidents at the school involving battles against these mysterious creatures, Mai learns that she is a HiME herself and is capable of summoning a Child, a mechanical creature capable of great utility and firepower. Now burdened with new responsibilities, Mai joins 12 other HiME as they safeguard the school from a threat they know little about all while protecting the ones closest to them.

A hero will never give up, never hide, never be defeated and never accept evil! Firmly believing these words, Masayoshi Hazama has been obsessed with superhero shows since childhood. By day, he earns his living as a famous model, and by night, he becomes the gallant hero Samurai Flamenco. Armed with only his superhero costume, he seeks to bring justice to the city and faces anybody who tries to break the law—even rebellious juveniles and people who litter on the street. Masayoshi's heroic antics later catch the attention of the public, leading to the fateful discovery of his identity by policeman Hidenori Gotou. Although initially telling Masayoshi to leave the crime-busting activities to the police, Gotou ends up joining him in his antics. However, things soon escalate from preventing littering and petty thefts to bizarre adventures that involve even the fate of the world. Together with their newfound comrades, Masayoshi and Gotou embark on a battle with the world and themselves in order to find the true meaning of being a hero—with or without superpowers.

Koguma, a reserved second-year high school student, has nothing—no parents, hobbies, friends, or goals. On her way home one afternoon, she visits a vehicle shop in hopes of acquiring a motor scooter. With only enough money to make ends meet, she is disheartened by the price tags and prepares to turn back. However, as she is about to leave, the shop's owner offers her a pre-owned Honda Super Cub for ten thousand yen. Believing that the motorcycle will help brighten her monotonous world, she accepts the deal. As Koguma journeys through her town on small adventures with her Super Cub, she begins to build irreplaceable friendships and eagerly advances toward her new life.

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.