The primary protagonist, Akito Tenkawa, is a boy with a mysterious past; once a resident of Mars\' Utopia colony, he escaped its destruction by the Jovian Lizards and arrived on Earth, with no memory of how he got there but a terrible fear of the invaders.

He hates fighting and only wants to be a chef. However, he is constantly called on to act as a pilot of one of the Nadesico\'s Aestivalis - humanoid combat robots.