Mr. Peabody and the Mermaid is a 1948 fantasy film starring William Powell and Ann Blyth in the title roles. Irene Hervey played Mr. Peabodys wife. The film was based on the 1945 novel Peabodys Mermaid by Guy and Constance Jones. Sequences were shot at the Weeki Wachee Springs in Florida.
Peabody goes on vacation with his wife Polly Irene Hervey to a Caribbean resort. While there, he hears singing coming from a distant key small island and takes his boat to do a little fishing. To his surprise, he reels in Lenore, a beautiful mermaid played by Ann Blyth.Although mute, Lenore is mischievous and childlike and more than a little bit alluring so much so that before long Peabody has taught her to kiss. He hides Lenore by letting her soak in a sudsfilled bathtub and then in the resorts fish pond. But confusion ensues as his wife thinks he has a big fish in their bathtub and later suspects him of infidelity with Cathy Livingston Andrea King, a vacationing singer. ........
Source: Wikipedia