Sora Harewataru, a hardworking girl from the magical kingdom of Skyland who idolizes the hero Captain Shalala, chases the Undergu Empire's Kabaton through a portal after he kidnaps baby Princess Ellee, landing with the infant on Earth in Sorashido City. When Kabaton attacks again, Ellee's power turns Sora into Cure Sky, and new friends Mashiro Nijigaoka, Tsubasa Yuunagi, and Ageha Hijiri join the fight as fellow Pretty Cures while Mashiro's grandmother searches for a way back to Skyland. Sora's catchphrase, 'It's hero time!', drives the team as they defend Ellee from the Empire's forces.