Colonel Yōichi Takagi commands the Earth Defense Force's elite Special Armored Battalion Dorvack, Earth's foremost defense against the Idelian invaders who landed in the Alps in 1999. Leading pilots Masato Mugen, Pierre Bonaparte, and Louise Oberon, Takagi deploys their advanced variable mecha—the transforming VV-54AR Mugen Calibur (jeep), VT-61LC Bonaparte Tulcas (tank), and VH-64MR Oberon Gazzette (helicopter)—directly against the alien threat when conventional Earth forces fail.