Splash too

After four years of living on an idyllic tropical island with his mermaid Madison, Allen Bauer returns to New York. However, she has to be careful not to get her legs wet. The slightest drop of moisture turns her legs into a mermaid's fin. During a visit to the Long Island Sea Aquarium, Madison discovers that her old companion, Salty the dolphin, has been captured and will be subjected to a dangerous experiment. Against Allen's wishes, Madison risks her marriage to save Salty from the hands of biologist Dr. Otto.