The enhanced version of Key's visual-novel, Planetarian: Hoshi no Hito, integrates additional narrative elements from its sequel, the Hoshi no Hito light-novel. Following the aftermath of nuclear and biological warfare that has desolated society, a young scavenger nicknamed "Junker" roams through a lifeless and quarantined city. While on a scavenging trip, he stumbles upon a service robot still servicing the customers in the abandoned planetarium located atop a department store. Though he is a practical man, he aids the robot in mending the projector of the planetarium. He is not aware that this selfless act will change their fate forever.