It is the love story of Vinicius and the Princess Lygia, a convert to Christ. The girl's happy and innocent life was rudely disturbed by a summons to the court of the profligate emperor. Arrived there, she found that Nero had given her to Vinicius, who had fallen passionately in love with her; but on the way to Vinicius' house she was rescued by the giant Ursus, one of her devoted attendants and a member of her own faith. They escaped in safety to the Christians, who were living in hiding in the city. The imperious nature of the youthful soldier for the first time in his life met resistance. He was so transported with rage and disappointment that he ordered the slaves from whom Lygia had escaped to be flogged to death, while he set out to find the girl who had dared to thwart his desire. His egotism was so great that he would have seen the city and the whole world sunk in ruins rather than fail of his purpose. For days and days his search was unceasing, and at last he found Lygia, but in making a second attempt to carry her off was severely wounded by the giant Ursus. Finding himself helpless in the Christians' hands, he expected nothing but death; but instead he was carefully and tenderly nursed back to health. Waking from his delirium, he found at his bedside Lygia--Lygia, whom he had most injured, watching alone, while the others had gone to rest. Gradually in his pagan head the idea began to hatch with difficulty that at the side of naked beauty, confident and proud of Greek and Roman symmetry, there is another in the world, new, immensely pure, in which a soul resides. As the days went by, Vinicius was thrilled to the very depths of his soul by the consciousness that Lygia was learning to love him. With that revelation came the certain conviction that his religion would forever make an inseparable barrier between them. Then he hated Christianity with all the powers of his soul, yet he could not but acknowledge that it had adorned Lygia with that exceptional, unexplained beauty, which was producing in his heart besides love, respect; besides desire, homage. Yet, when he thought of accepting the religion of the Nazarene, all the Roman in him rose up in revolt against the idea. He knew that if he were to accept that teaching he would have to throw, as on a burning pile, all his thoughts, ideas, ambitions, habits of life, his very nature up to that moment, burn them into ashes and fill himself with an entirely new life, and from his soul he cried that it was impossible; it was impossible! Before Vinicius had entirely recovered Nero commanded his presence at Antium, whither the court was going for the hot summer months. Nero was ambitious to write an immortal epic poem which should rival the "Odyssey," and in order that he might describe realistically a burning city, gave a secret command while he was in Antium that Rome should be set on fire.