Near a forest in Austria there lives an old fisherman, his wife, and their foster daughter, Undine. The nearby wood is said to be inhabited by spirits who are enemies of the mortal human beings living outside the forest.
One day, the young knight Sir Huldbrand of Ringstetten is traveling through the forest when a storm breaks. As he rides through the gloomy wood, he is pursued and tormented by manifestations of unearthly folk. At last he comes to the edge of the forest and takes refuge in the fisherman’s cottage, where he is given food and shelter.
Sir Huldbrand is amazed by the beauty of young Undine, who asks him to tell the story of his adventures in the forest. The fisherman, however, forbids the telling and cautions that it is unwise to talk of spirits at night. Undine—rebellious, mischievous, and untamed—disappears into the night when her foster father reproves her.
The fisherman and the knight call for her to return, but their voices are lost in the noise of the wind and of the rain. As the storm increases, they become more worried and finally set out in search of her. It is Sir Huldbrand who finds her, safe and sound in the leafy bower where she is hiding. When he returns with her to the fisherman’s cottage, he tells her of his adventures in the forest. The storm rages so furiously that the cottage and its four inhabitants become cut off by encircling floods.
Sir Huldbrand relates how it came about that he traveled through the forest. He fell in love with Bertalda, a haughty lady who insisted that he prove his love and courage by a journey through the dreadful wood. At that point in his tale, Undine becomes jealous of the lady and bites the knight’s hand. A few days later, a priest, who loses his boat in the swirling stream, takes refuge on the island. That night he marries Undine and Sir Huldbrand. The marriage changes the girl completely. She becomes submissive, considerate, and full of affection. She gains a soul.
After the floodwaters subside, the couple leave for the knight’s home, Castle Ringstetten. On the way, they go to pay homage to the duke of the domain, and in his hall they met Bertalda. Undine takes Bertalda to her bosom and announces that she has a surprise for her. Shortly before, Undine told her husband that she really is a water spirit, and that she can live on earth only until he rejects her love; then Kühleborn, who rules the waters, will call her back to her water home. She lived with the fisherman and his wife since she was a child, having appeared at their cottage on the evening of the day when their own child had, apparently, been drowned.
Undine’s surprise, which she arranges with the help of Kühleborn, is to reveal that Bertalda is the long-lost child of the fisherman and his wife. At first the proud lady refuses to accept them as her true parents. When she demands proof of the story, she is identified by a birthmark on her body. Bertalda’s foster parents are disgusted with her and cast her off. The next day, Bertalda accosts Undine and Sir Huldbrand outside the duke’s castle. Dressed as a poor fishing girl, she is ordered to sell food to learn humility and the dignity of toil before being allowed to rejoin her real parents. Pitying her, Undine and Sir Huldbrand insist that she live with them at Castle Ringstetten.
Life does not always go smoothly at the castle. One day, Undine, who is loved by the servants, orders the well to be sealed....
(The entire section is 941 words.)