Following a failed Mars probe return, Tokyo is plagued by the emergence of hostile beings known as 'Ancients' that defy conventional weaponry. Amid global chaos, hope arises in the form of the exclusive MARS suit tailored to combat these foes, accessible only to individuals with specific genetic markers. Takeru Hinata, a troubled youth with a mysterious past, emerges as one of the chosen few capable of piloting this specialized armor. Teaming up with the AAST, a specialized law enforcement unit dedicated to eradicating the Ancients, Takeru confronts both personal demons and the enigmatic invaders to unravel the truth behind Earth's newfound threats.