Sinbad The Sailor sails to deliver a cursed prince to a dangerous island in the face of deadly opposition from a powerful witch. Sinbad must deliver a prince transformed into a monkey to the lands of the Ademaspai to restore him to his human form in time for his coronation. On the way he must contend with the evil witch Zenobia, her son and their magic, and several nasty-looking Ray Harryhausen beasties.