The video shows a cartoon mermaid with red hair and a green tail swimming underwater. She is accompanied by a large blue whale and a school of small fish. The mermaid is seen riding on the whale's back, playing with the fish, and interacting with a dolphin. The underwater setting is depicted with various sea plants and coral. The colors are vibrant, with the mermaid's red hair and green tail contrasting against the blue of the whale and the sea.