Naples, 1959. Pure Mathematics professor Renato Caccioppoli, Bakunin's grandson, is a tortured soul. Recently discharged from the psychiatric hospital, left by his wife, and increasingly disillusioned with academia and the Communist Party, he lives his last days with painful detachment.

In 1914, a cruise ship sets sail from Naples to spread the ashes of beloved opera singer Edmea Tetua near Erimo, the isle of her birth. During the voyage, the eclectic array of passengers discovers a group of Serbian refugees aboard the vessel. Peace and camaraderie abound until the ship is descended upon by an Austrian flagship. The Serbians are forced to board it, but naturally they resist, igniting a skirmish that ends in destruction.

Who is the mysterious stranger Cecilia met on the street? Why is he suspicious of everyone? She is happily married, has a lovely child and a good job: yet she decides to join him and to become his lover, sharing his destiny right up to its tragic conclusion.

Young radical Riccardo returns home after hiding in South America for five years, only to find out that his comrades either gave up their ideals or turned to drugs, while all they fought for seems to have set the stage for near-anarchy.