On their first day of high school shy Ayumi Nonomura and taciturn Tatsuki Iizuka become lost on the immense campus of Kamizono Academy. An irresistible force of nature named Torako Kageyama accompanied by her best friend Suzume Saotome appears in front of them. Led, sometimes pushed, by Torako, the girls and their classmates work through problems of school, home and adolescence.

Shiratori Ryuushi is a young artist-in-training, about to start studying at a vocational school. Arriving at his new lodgings, Narutakisou, he finds himself the focus of attention for the collection of weirdos that inhabit the place. He also meets and falls for the landlady, Aoba Kozue, who seems to be both lovely and charming. However, Kozue is not what she seems to be... in fact, she's more.

An adaptation of the visual-novel by Key, Planetarian: Hoshi no Hito combines the story of the original work with an expansion that extends the narrative with content from the Hoshi no Hito light-novel sequel. In the future after much of the world has been devastated by nuclear and biological warfare, a young scavenger or "Junker" exploring a quarantined and abandoned city comes across a service robot still faithfully awaiting customers in the rooftop planetarium of a department store. Against his pragmatic instincts he helps the robot repair the planetarium's projector: a decision which will change both their fates.

Several years ago, local heroines—superhero characters who represent towns and perform stage shows in order to raise their town's acclaim—had a boom in popularity. The most famous of these local heroines, Kamidaio, is scheduled to perform in the small town of Hinano, much to the excitement of Mikan Kise's little sister Yuzu. Unfortunately, when Mikan takes Yuzu to the show, she finds out that it has been canceled. She promises her distraught sister that she'll make sure she can see the show. Desperate not to let her down, Mikan asks her classmate, the local heroine fanatic An Akagi, for help. Mikan and Ann put on their own Kamidaio performance clad in homemade costumes, which the kids in the audience love despite its lack of production value. The show is recorded by the student council president Misaki Shirogane, who posts it online to garner attention. Misaki is from a family of politicians and has taken it upon herself to revitalize Hinano. Impressed by their show, she recruits Mikan and An to become the official local heroines of their town. As the group works to improve their shows, they enlist the help of a variety of colorful individuals. [Written by MAL Rewrite]