After a fierce battle to defend the city of Oroscopa from Massinissa's army, Hiram, a Carthaginian leader, is wounded and rescued, then nursed back to health by the young Roman woman Fulvia, who quickly falls in love with him.
With Carthage under threat from Rome, the Carthaginian Council, acting on Massinissa's orders, sentences him to exile. Carthage teeters on the edge of collapse, and Hiram is forced to return in secret, intent on taking away with him the woman he loves, Ophir, the daughter of Hermon, the head of the Council. Ophir is also in love with him, though her father has arranged a marriage to Tsour, a young Carthaginian she has known since childhood.
Fulvia has also arrived in Carthage, seeking Hiram, and has fallen into the hands of Phegor, the commander of the sacred guards. Phegor is attracted to Fulvia and would spare her life, but the Carthaginian people, seeing her as a Roman, have decided to sacrifice her in the temple of Moloch. Hiram manages to save Fulvia, but in his attempt to free Ophir as well, he is captured himself.
With the help of his friends Sidone and Astarito, Hiram escapes from prison and prevents Ophir's marriage to Tsour. He also regains the friendship of the leader of the mercenaries, Thala, with whom he had fought in Oroscopa. Seeing the depth of their bond, Tsour realizes the great love between Ophir and Hiram and decides not to oppose their union.
The Carthaginian Council splits: Hiram and Tsour want to take up arms against the Romans, while Phegor advocates negotiation. In truth, Phegor is stalling, secretly aiding the enemy to secure power once the city falls. Hermon decides to support the battle line and marshal Carthaginian forces.
In the clash at Birsa, Hiram, Tsour, Thala, and Asdrubale fight alongside their allies, but they are eventually defeated by Scipione l'Emiliano, assisted by Numidian troops under Gollussa. The outcome shakes Carthage's resolve and foreshadows a harsher fate.
Meanwhile, Fulvia, having yielded to Phegor, secures a ship, and Sidone, Astarito, and Ophir—after they rescue the wounded Hiram from the battlefield—set course for the open sea. Carthage burns, its streets and homes engulfed in flames, and Phegor's hopes for Roman aid crumble as the city succumbs to the catastrophe.
In a final, desperate moment on the balcony, Fulvia sacrifices her life to spare Hiram, sealing the lovers' fates with a quiet, costly act. Far at sea, the battered crew watches Carthage burn on the horizon, while the fates of Ophir and Hiram hang in the balance of a new, uncertain world.
