Xanten am Rhein, 1870/1871. Roffer Rottwinkel has two sons. His favorite is Mathias, whom he prefers to Lonius, a quiet and introspective man. Lonius, for his part, is shyly revering Christine ... and his brother's in love with her, too. For this reason, the father sends Lonius away, to fight in the Franco-Prussian War, which turns the introverted boy into a brave and strong man. Highly decorated, he returns home. In the meantime, his brother Mathias and Christine are unhappily married. Mathias is slipping more and more and finally becomes a con man. As Lonius is still very much in love with Christine, he wishes to save his father's business from ruin and rebels against his brother, who now goes to extremes.