The Rainbow Fish was the most beautiful fish in the sea due to his colorful, shiny scales. However, he was lonely because his scales made the other fish feel inferior. When a small blue fish asks for a scale, the Rainbow Fish refuses angrily. Later, a wise octopus tells the Rainbow Fish to share his scales to find happiness. Reluctantly, the Rainbow Fish gives a scale to the blue fish and discovers joy in sharing. He then gives scales to all the other fish. Though now less colorful, the Rainbow Fish is happy and accepted by his new friends.