As Garibaldi's troops begin the unification of Italy in the 1860s, an aristocratic Sicilian family grudgingly adapts to the sweeping social changes undermining their way of life. Proud but pragmatic Prince Don Fabrizio Salina allows his war hero nephew, Tancredi, to marry Angelica, the beautiful daughter of gauche, bourgeois Don Calogero, in order to maintain the family's accustomed level of comfort and political clout.

After a novice nun learns of the sudden death of her parents, she leaves the convent to manage the family business and look after her teenage sister. Both of them fall prey to a womanizing mechanic with psychopathic tendencies.