"The Fisherman and His Wife" is a German fairy tale collected by the Brothers Grimm. It tells the story of a poor fisherman who catches a magical fish that grants him wishes. His wife becomes increasingly greedy, and with each wish, she demands more and more until she wants to become queen of the world. The fisherman is eventually forced to return the fish to the sea to undo his wife's wishes and restore their simple life.

The fairy tale teaches that greed and excessive ambition can lead to ruin. The fisherman's wife's unquenchable desire for more and more causes her to lose everything and return to her previous state of poverty. It also emphasizes the importance of contentment and the value of a simple life, rather than constantly striving for more.