The story is set during the time of the Five Days War of 1848 between Italy and Austria. Clara, daughter of a rich Milan trader who deals with the Austrian army, is in love with Enrico, a devoted member of the Carbonaro revolutionary organization. Unfortunately, her father wants her to marry Count Severi, a young aristocrat who is dissolute, penniless and pro-Austrian. Denounced by Count Severi for his political activities, Enrico is forced to flee, but while crossing the Ticino river he is hit by an Austrian bullet. Hearing that he is dead, Clara in despair marries Count Severi, but the marriage does not turn out to be a happy one. The Count believes his wife to be an adventuress with a lover, and so he decides to poison her and thereby gain the considerable property that she has had bestowed by her father. Then Enrico, who is not dead, returns to Milan and tries to find Clara. He learns that she died the day before and sadly goes to pay his respects at the chapel where her body lies