"Prefectural Earth Defense Force" is a comedic science fiction anime that blends absurd humor with a satirical take on bureaucratic inefficiency and small-town life. The story is set in a rural Japanese prefecture where a group of underqualified and unmotivated civil servants is unexpectedly tasked with defending Earth from alien invasions. The series centers on the Prefectural Earth Defense Force, a ragtag team of government employees who are ill-prepared for their new responsibilities. Their lack of training, resources, and enthusiasm contrasts sharply with the gravity of their mission, creating a series of humorous and often chaotic situations.

The main characters include the bumbling but well-meaning leader, who struggles to maintain order within the team; a disinterested office worker who joins the force out of obligation; and a young recruit who is overly enthusiastic but lacks practical skills. The team is supported by a small cast of eccentric coworkers and a stern but equally inept supervisor. Together, they face a variety of alien threats, ranging from comically inept invaders to more serious adversaries, all while navigating the challenges of their day-to-day bureaucratic duties.

The narrative unfolds through episodic encounters with alien forces, each presenting a new challenge that highlights the team's incompetence and resourcefulness in equal measure. Despite their shortcomings, the members of the Prefectural Earth Defense Force often manage to save the day through a combination of luck, improvisation, and occasional moments of genuine teamwork. The series uses its premise to explore themes of perseverance, camaraderie, and the absurdity of institutional systems, all while maintaining a lighthearted and humorous tone. The interplay between the characters' personal quirks and their shared mission drives much of the story, creating a balance between slapstick comedy and moments of unexpected sincerity.