Nobita gets what he wants and immediately regrets it. A world running on magic should be his fantasy, except he's still terrible at it, still powerless, still the same kid in a different ruleset. The real gut of this one is watching him chase down a Moshimo-box his mom threw away because he can't accept that changing the world doesn't change him.
Nobita uses Doraemon's wish-granting box to transform the world into a place where magic reigns supreme. Science vanishes overnight, replaced by spellcasting and enchantments that everyone masters instantly. Everyone except Nobita, naturally. His usual fumbling with incantations leaves him desperate to undo the change, but the device that started it all is gone for good. When a mysterious professor and his daughter arrive with urgent warnings, the situation spirals beyond personal frustration. An ancient celestial body called the Star of the Underworld hurtles toward Earth's orbit, threatening catastrophic destruction. The only solution lies in a dangerous expedition to the Underworld itself, where Nobita and his friends must confront the Underworld King and pierce its heart with a silver dart. The prophecy is clear. The stakes are planetary. What begins as Nobita's selfish wish becomes a race against apocalypse. Armed with magic they barely understand, the group descends into realms where danger lurks behind every shadow and ancient powers stir once more.