Disobeying her father's strict orders, a free-spirited young mermaid named Ariel ventures to the ocean surface. Soon she loses her heart to a human prince. To be come human herself, Ariel makes a deal with the powerful, malicious sea witch Ursula, endangering not only herself but the entire un dersea domain of King Triton, her father. Will Ariel find the courage to face evil and make her dream come true?