Sophie, a reserved worker in a hat store, experiences an upheaval in her life when a good-looking yet enigmatic wizard named Howl carries her away. Their camaraderie awakens the envy and spite of the egotistical Witch of the Waste, who retaliates by casting a curse on Sophie. Accompanied by Howl, Sophie embarks on a life-altering journey, boarding his astonishing airborne castle and venturing into a fantastical realm, determined to undo the hex.