A millennium has passed since the devastating "Seven Days of Fire," a nuclear conflict that wiped out most life on Earth. In the aftermath, humanity struggles to survive against a hostile jungle thriving among the ruins, infested with toxic spores and giant insects that relentlessly encroach on the dwindling human settlements.
The peaceful farming kingdom known as the "Valley of the Wind" remains untouched by the jungle due to its coastal location. Here, the Valley's spirited young princess, Nausicaä, sees her tranquil realm disrupted when an airship from Tolmekia crashes into their territory. After discovering a mysterious, pulsating artifact within the wreckage, Tolmekia launches a military assault on the Valley, aiming to reactivate a dangerous weapon from the ancient war. Nausicaä is forced to stop the Tolmekians from igniting another catastrophe that would doom humanity, all while protecting her people from the spreading toxic jungle.