Legendary adventurer Sinbad (Patrick Wayne) stops in a port town to visit his friend Prince Kassim (Damien Thomas), only to find the city walls locked and no one there to greet him except an evil witch, Zenobia (Margaret Whiting), and her monstrous henchmen. Kassim's sister, Princess Farah (Jane Seymour), finds Sinbad and informs him her brother has been transformed into an ape, so now it's up to Sinbad to find the magic shrine that may be the only hope for restoring Kassim to his human form.