Eureka Seven is a story set in a distant future in another planet, where the humans who settled there were threatened by a mysterious phenomenon named "Summer of Love" a few years before, but according to official history, it was stopped by a military researcher called Adrock Thurston who gave his life to protect mankind.

Renton Thurston, the series's main character and Adrock's son, is a fourteen-year-old boy who idolizes Holland, the leader of a group of mercenaries called Gekko State, which apparently are just an independent militia that stands against the policies of a belligerent and oppressive government, but their true objective is to make contact with the "coralians", sentient hidden creatures that also inhabit that world, in order to prevent the United Federation's imminent war against them, for the control of the planet.

The story revolves around Renton's joining Gekko State and his budding relationship with the mysterious Eureka, a female member of Gekko State and pilot of the LFO Nirvash typeZERO. When Renton and Eureka pilot the Nirvash together, powered by the mysterious "Amita Drive", it becomes almost invincible, and can liberate a massive amount of rainbow colored energy in a phenomenon named "The Seven Swell". (Wikipedia)