In the wake of a recent conflict between Earth and its space colonies, the Earth Sphere Unified Nation is formed, ushering in a period of unity and progress in A.C. 196. Most Gundam pilots opt to symbolize this newfound peace by sending their mobile suits into the sun. However, their intentions are disrupted by the sudden rise of Mariemaia Khushrenada, who claims lineage to the late dictator Treize and seeks world domination. Feeling compelled to safeguard their hard-earned peace, Heero Yuy, Trowa Barton, Duo Maxwell, and Quatre Raberba Winner retrieve their Gundams to thwart Mariemaia's ambitions. As they gear up for this crucial mission, they face a formidable challenge in their former comrade Wufei Chang, who now fights on the side of the rebellious Mariemaia.