The novella tells the story of Hauke Haien, related to the narrator by a schoolmaster in a small town in Northern Frisia.

Over time he becomes very familiar with the dykes along the local coast and begins to wonder if it would not be better to make them flatter on the sea side so as to reduce their windage during floods.

However, during a storm surge several years later, the older dykes break and Hauke has to witness Elke and their daughter, Wienke, being swept away by the water.

The novella ends with the schoolmaster recounting that after the flood the mysterious horse skeleton was once again seen lying on the small island off the coast.

Thomas Mann called it a "tremendous tale, with which Storm took his conception of the novella, as epic sister of drama, to unprecedented heights".