"Code Geass: Lelouch of the Re;surrection" is a continuation of the "Code Geass" series, set after the events of "Code Geass: Lelouch of the Rebellion R2." The story takes place in a world where the Holy Britannian Empire has been dismantled, and the United Federation of Nations (UFN) governs the world. However, peace remains fragile as remnants of Britannia and other factions seek to destabilize the new order.

The narrative centers on Lelouch vi Britannia, who was presumed dead after the Zero Requiem, a grand scheme to bring peace by sacrificing himself. In this film, Lelouch is resurrected through a combination of advanced technology and the mystical power of Geass. His return is orchestrated by C.C., his immortal companion, who seeks his help to resolve a new crisis. Lelouch, now operating under the alias "L.L.," is drawn back into the world of political intrigue and warfare.

The plot revolves around a conflict in the kingdom of Zilkhstan, a nation rich in sakuradite, a vital resource for advanced technology. A militant group known as the Zilkhstan Royalists, led by the enigmatic Shalio, seeks to overthrow the ruling government and establish a new order. Shalio possesses a powerful Geass ability, which allows him to manipulate others into becoming his loyal followers. This Geass poses a significant threat to global stability, prompting the UFN and the Black Knights to intervene.

Lelouch, alongside C.C., Suzaku Kururugi (who now operates as the masked vigilante Zero), and Kallen Stadtfeld, becomes entangled in the conflict. The group must navigate complex alliances, betrayals, and the resurgence of Geass-related powers to prevent Shalio from achieving his goals. Lelouch's strategic brilliance and moral ambiguity are once again put to the test as he balances his desire for redemption with the necessity of making difficult choices.

The film explores themes of resurrection, legacy, and the consequences of wielding power. It also delves into the relationships between Lelouch and his allies, particularly his bond with C.C., which evolves as they confront new challenges together. The story maintains the series' signature blend of political drama, mecha battles, and supernatural elements, culminating in a resolution that ties together the threads of Lelouch's journey while leaving room for future possibilities.