When he was a little boy, Allen Bauer (Tom Hanks) fell off a boat. He would’ve drown, but he was saved by what he believed to be a little girl mermaid. Now, it is many years later and he is a fruit importer in New York City with his brother Freddie Bauer (John Candy). He is single and often wonders about the little girl who saved him. One day, he falls off another boat and wakes up on the beach. A beautiful blonde woman is there, but she mysteriously disappears into the water. A few days later, she shows up naked at the Statue of Liberty. Allen takes her in. She quickly learns English and chooses the name of Madison (Daryl Hannah). Madison is his dream come true, even though she is very cryptic about who she is and where she comes from. On her tail is Dr. Walter Kornbluth (Eugene Levy), who believes she is a mermaid and wants to make his name known.