In the futuristic world of FC 60, Earth's orbit teems with space colonies where humanity resides. Every four years, nations clash in a grand tournament using colossal robots known as Gundams to determine colonial supremacy. Domon Kashuu, the chosen champion of Neo-Japan, enters the fray not solely for victory but to unravel the truth behind his brother's alleged involvement in their parents' demise, the vanishing of the ominous Dark Gundam, and to seek justice.