Set in the future, a giant fighting machine called the Aquarion is humanity's only effective weapon in the fight against the technologically advanced...

Koshiro and Nanoka fall deeply in love, then discover they are the children of their divorced estranged parents... making them brother and sister....

Ten years ago, the forces of the Erebonian Empire invaded the Kingdom of Liberl, nearly reaching the heart of the Capital City before Cassius Bright...