In the beginning, the most beautiful fish in the ocean does not want to share one of his shining scales with a little blue fish. All the other fish in the sea ignore him after this and he does not understand why. He goes to the wise octopus for advice, and she tells him to give away his scales. Rainbow Fish reluctantly gives away all but one of his scales. In the end, he is less beautiful than he was before, but he has new friends and is now the happiest fish in the sea.