The plot weaves several episodes with several groups of people, Roman families, youth gangs and young love couples, who spend a Sunday at the beach of Ostia.
Carlo Rutelli falls in love with the beautiful variety singer Yvonne la Nuit, but his father opposes the wedding. World War I breaks out and Carlo is killed while Yvonne has a son, but on orders from Carlo's father, she is told he is dead. Her career descends and only Nino, an art partner, remains close to her and helps her earn her living by singing in taverns.
In ancient Rome a love story blossoms between Fabiola, daughter of a senator, and Rhual, a Gallic gladiator. After Fabiola's father is killed, the Romans blame the Christians and the persecution begins. Rhual confesses to being a Christian, is accused of the murder and sentenced to fight to the death in the arena.
