Quo Vadis by Henryk Sienkiewicz begins with the young and valiant patrician Vinicius coming to his uncle Petronius, who is a writer, a connoisseur of art, and Caesar Nero’s friend. Vinicius is fascinated with Lygia, who was brought to Rome as a hostage and grew up in the home of the noble Aulus.

At Aulus’s, Vinicius speaks tenderly to Lygia, and a reciprocal feeling is born in the young woman’s heart. But for some reason, she draws a fish on the sand.

Petronius tells Nero that Vinicius is in love with the hostage. Nero promises to Petronius to take her to the palace and give her to Vinicius. Lygia does not want to become Vinicius’s concubine and so decides to flee.

The sly Greek Chilo volunteers to find Lygia. Soon he figures out that the fish is a secret sign used by Christians. Pretending to be a Christian, Chilo sneaks into their circle.

The Apostle Peter arrives in Rome. All Christians of the city come to listen to his night sermon. Chilo brings Vinicius, who hopes to see Lygia. The Apostle Peter impresses the young patrician with his simultaneous simplicity and grandeur. Vinicius understands that Lygia, as a Christian, will never become his concubine.

The young patrician follows Lygia after the sermon and tries to carry her away. But her compatriot, the servant Ursus, prevents him from doing this by hitting him on his head. Vinicius loses consciousness and is taken to Lygia’s humble abode, where the physician Glaucus takes care of him. Lygia herself nurses the young man tenderly. Soon Vinicius feels that his lust gives way to real, deep love. But Lygia cannot love the young man, who is still a pagan, and she decides to part with him.

Vinicius returns home, but he longs for Lygia and often remembers the Apostle Paul, the wonderful man whom he met while staying with Christians.

Now Vinicius abhors the immorality of the Roman nobles. Chilo brings Vinicius to the Apostles. There Vinicius asks Peter and Paul for Lygia’s hand in marriage and promises to try to understand and embrace Christ’s teachings. Peter blesses the the two.

But the delirious Nero dreams of a great and terrifying performance, and his acolytes set Rome on fire. Trying to rescue Lygia, Vinicius hurries to an underground prayer house where he sees the Apostle Peter comforting Christians. Peter leads him to Lygia and then baptizes him.

To save Nero and themselves from the enraged crowds, the patricians spread rumors that Christians are to blame for the fire. Chilo is ready to betray all Christians and primarily Vinicius and Lygia.

Petronius warns his nephew that soon Christians will be persecuted. But Vinicius fails to rescue Lygia. She is put in prison.

Peter receives a revelation: Christ wants to build his capital in this city of Satan. Meanwhile, Christians are tortured and die for Christ’s sake.

Vinicius sneaks into the dungeon and spends three days with Lygia, who is sick.

Nero’s performance continues. In the arena, Vinicius sees Ursus and then a huge aurochs to whose horns Lygia is tied. Ursus grabs the aurochs by the horns and wrings the wild beast’s neck. Fearing the exultant crowd, Nero grants Ursus and Lygia life and liberty.

Lygia and Vinicius beg Peter to leave Rome, where persecutions still rage. He finally succumbs, but as he walks along the Appian Way, he sees Christ.

“Quo vadis, Domine?” (“Where do you go, oh Lord?”) the Apostle asks Christ. Christ answers: “If thou desert my people, I am going to Rome to be crucified a second time.”

In the end, Peter and Paul die martyrs’ deaths for Christ. As for Vinicius and Lygia, they become husband and wife and live peacefully and happily in Sicily.