"Infinite Stratos" is set in a world where advanced exoskeletal weapons known as Infinite Stratos (IS) have revolutionized warfare and technology. These powerful suits are unique in that only women can operate them, making them the dominant force in military and societal structures. The story centers around Ichika Orimura, a young man who inadvertently becomes the first male capable of piloting an IS. This anomaly thrusts him into the spotlight and enrolls him at the prestigious IS Academy, an institution dedicated to training IS pilots.

At the academy, Ichika finds himself surrounded by highly skilled female pilots, each with their own distinct personalities and motivations. Among them are Houki Shinonono, his childhood friend who harbors unresolved feelings for him; Cecilia Alcott, a proud British representative pilot; Lingyin Huang, a fiery and competitive Chinese pilot; Charlotte Dunois, a kind-hearted French pilot who initially disguises herself as a boy; and Laura Bodewig, a stoic German pilot with a military background. These characters form the core of the narrative, with their interactions and rivalries driving much of the plot.

The series blends elements of science fiction, action, and romantic comedy, with a focus on the challenges Ichika faces as the sole male IS pilot. His presence disrupts the established order, leading to both admiration and resentment from his peers. The story explores themes of gender dynamics, personal growth, and the responsibilities that come with wielding immense power. As Ichika navigates the complexities of his new life, he becomes entangled in various conflicts, including international competitions, political intrigue, and the machinations of shadowy organizations seeking to exploit IS technology.

Throughout the series, the relationships between Ichika and the female pilots evolve, often oscillating between camaraderie and romantic tension. The narrative also delves into the broader implications of IS technology on global politics and society, highlighting the potential for both progress and peril. The action sequences, centered around IS battles, showcase the unique capabilities of each suit and the strategic prowess of the pilots. Despite the high-stakes scenarios, the series maintains a lighthearted tone, with humor and character-driven moments balancing the more intense plot developments.