A millennium has passed since "Seven Days of Fire," an apocalyptic war that almost wiped out human civilization. Since then, the earth is covered with an ever-growing "Sea of Corruption," a vast forest of fungi that secretes poisonous miasma and invasive spores, along with large and deadly insects inhabit within.

In order to fight for more habitable lands unpolluted by the Sea of Corruption, the Kingdom of Torumekia has declared war against the Dorok Empire. Nausicaä, princess and heir of a small city-state named "Valley of the Wind" which pledged alliance with Torumekia, is now forced to join Torumekian to invade Dorok Empire. This war will change her life and the fate of human race forever.