Flood City is the last city on Earth not covered by water, the site of the last battleground between the spaceship-dwelling Chemical Barons, who want to return to the planet, and the Star Guard, controllers of the city who want to keep control of the planet away from the Chemical Barons. Max, born in the city, just wants to play music with his band and get the courage to ask his crush, the drummer Djinna, out finally; Ato, the young Chemical Baron, joins a crew that was supposed to be on routine surveillance but actually discovers deadly schemes intent on wiping out Flood City entirely. These two young enemies worlds collide, and they must work together to save the Earth.