The ruler of the evil Phantom Empire, Queen Mirage, begins her invasion on Earth using an army of Choiarks and powerful monsters called Saiarks. Pretty Cures are dispatched to fight against the Phantom Empire threat. Hime Shirayuki, a princess from the Blue Sky Kingdom who was given the power to become Cure Princess by a being named Blue, flees to Japan when her kingdom is invaded by the Phantom Empire. They defended the Earth against the Phantom Empire.