In the year 2010, the Holy Empire of Britannia is establishing itself as a dominant military nation, starting with the conquest of Japan. Renamed to Area 11 after its swift defeat, Japan has seen significant resistance against these tyrants in an attempt to regain independence. Lelouch Lamperouge, a Britannian student, unfortunately finds himself caught in a crossfire between the Britannian and the Area 11 rebel armed forces. He is able to escape, however, thanks to the timely appearance of a mysterious girl named C.C., who bestows upon him Geass, the Power of Kings. Realizing the vast potential of his newfound power of absolute obedience, Lelouch embarks upon a perilous journey as the masked vigilante known as Zero, leading a merciless onslaught against Britannia in order to get revenge once and for all.

One year has passed since the Black Rebellion, a failed uprising against the Holy Britannian Empire led by the masked vigilante Zero, who is now missing. At a loss without their revolutionary leader, Area 11's resistance group—the Black Knights—find themselves too powerless to combat the brutality inflicted upon the Elevens by Britannia, which has increased significantly in order to crush any hope of a future revolt. Lelouch Lamperouge, having lost all memory of his double life, is living peacefully alongside his friends as a high school student at Ashford Academy. His former partner C.C., unable to accept this turn of events, takes it upon herself to remind him of his past purpose, hoping that the mastermind Zero will rise once again to finish what he started, in this thrilling conclusion to the series.

On December 24, 2029—the day colloquially known as the Lost Christmas—the Apocalypse Virus spread across Japan, bringing death to its citizens and plunging the country into utter chaos. In an effort to establish order, the United Nations sends the GHQ to assist with the crisis by containing the outbreak while removing all political autonomy in the process. A decade later, the country still lives under their control, unable to break free from their draconian rule. Frustrated with the state of the nation, a resistance group named the Funeral Parlor aims to liberate Japan from the GHQ. Led by the charismatic Gai Tsutsugami, the group plots to steal a vial containing the Void Genome to further their goals. The vial falls into the hands of internet vocalist Inori Yuzuriha, who ends up being hunted by the GHQ's Anti-Bodies forces. Having nowhere to go, she seeks refuge in a warehouse where she meets Shuu Ouma—a socially awkward high school student who is a huge fan of her music. Shuu gets dragged into the conflict the moment he rescues Inori, and the Void Genome shatters in his hand, granting him the Power of the Kings. While learning how to control his grand new ability, Shuu must now fight to liberate Japan from its cruel oppressors.

Twenty-two-year-old Eikichi Onizuka—ex-biker gang leader, conqueror of Shonan, and virgin—has a dream: to become the greatest high school teacher in all of Japan. This isn't because of a passion for teaching, but because he wants a loving teenage wife when he's old and gray. Still, for a perverted, greedy, and lazy delinquent, there is more to Onizuka than meets the eye. So when he lands a job as the homeroom teacher of the Class 3-4 at the prestigious Holy Forest Academy—despite suplexing the Vice Principal—all of his talents are put to the test, as this class is particularly infamous. Due to their utter contempt for all teachers, the class' students use psychological warfare to mentally break any new homeroom teacher they get, forcing them to quit and leave school. However, Onizuka isn't your average teacher, and he's ready for any challenge in his way. Bullying, suicide, and sexual harassment are just a few of the issues his students face daily. By tackling the roots of their problems, Onizuka supports them with his unpredictable and unconventional methods—even if it means jumping off a building to save a suicidal child. Thanks to his eccentric charm and fun-loving nature, Class 3-4 slowly learns just how enjoyable school can be when you're the pupils of the Great Teacher Onizuka.