"The Fisherman and His Wife" is a German fairy tale collected by the Brothers Grimm, tale no. 19. Its theme was used in The Tale of the Fisherman and the Fish, an 1833 poem by Aleksandr Pushkin. Virginia Woolf has her character Mrs. Ramsey in To the Lighthouse read a version of the story to her son, James. Günter Grass's 1977 novel, The Flounder, is loosely based on the fairy tale, as are Emanuele Luzzati's version, Punch and the Magic Fish, and Ursula LeGuin's novel The Lathe of Heaven.

The synopsis is the following:

One day the fisherman catches a fish, which claims to be an enchanted prince, and begs to be set free. The fisherman kindly releases it. When his wife hears the story, she says he ought to have had the fish grant him a wish. She insists that he go back and ask the flounder to grant her wish for a nice house.

The fisherman returns to the shore but is uneasy when he finds that the sea seems to becoming turbid, as it was so clear before. He makes up a rhyme to summon the flounder, and it grants the wife's wish. The fisherman is pleased with his new wealth, but the wife is not and demands more, and demands that her husband go back and wish that he be made a king. Reluctantly, he does, and gets his wish. But again and again, his wife sends him back to ask for more and more. Each time, the flounder grants the wishes with the words: "just go home again, she has it already" or similar, but each time the sea grows more and more fierce.

Flounders are a group of flatfish species. They are demersal fish, found at the bottom of oceans around the world; some species will also enter estuaries

More Info: en.wikipedia.org