Several months after a probe returning from Mars burns up during reentry, strange creatures dubbed "Ancients" begin to appear throughout Tokyo. Aggressive and dangerous, they cannot be killed with ordinary weapons. As scientists struggle to find the cause of their sudden appearance, the monsters wreak havoc across the world. Humanity finds hope in the form of the MARS suit—a new weapon developed to take down these enemies. The suit, however, can only be worn by those with specific DNA. Enter Takeru Hinata, an ordinary teen with a troubled past and one of the few capable of piloting the only weapon against the Ancients. With the help of the AAST, a special police force established to defeat the dangerous creatures, the young man battles against demons both personal and global whilst trying to discover the true nature of Earth's new aggressors.

Anime based on a 1986 novel.

A young boy uses his scientific skills to fight enemies.

Despite being a refugee from an extinct planet, having an alcoholic as a father and an airhead for a mother, Maris' biggest problem is that she's a Thanatosian. Considering that Thanatosians are six times stronger than the average Earthling it shouldn't be such a curse, especially in a galaxy where violence is rife. But the accidental destruction she wreaks on everything she touches —even with the exotic alloy restraints she wears— means she's constantly in debt. Every mission she's assigned to by the Inter-Galactic Space Patrol becomes a cash-drain when all the damages are docked from her wage. But when she's selected to rescue the rich and sexy Kogane Maru it's like a dream come true. After setting him free from the terror of his ruthless kidnapper his eternal gratitude will surely guarantee marriage —and an end to all her financial headaches.