Memphis, the 17-year-old Pharaoh of ancient Egypt ruling 3,000 years ago, begins as ruthless, spoiled, and prone to violence. His authoritarian nature surfaces when he captures Carol, a time-traveling archaeology student from modern America. As son of the deceased King Nefermaat, Memphis shares a fraught relationship with his half-sister Isis, High Priestess ruling Lower Egypt. Isis obsessively desires marriage according to royal tradition, creating stark conflict with Carol's modern values. Memphis struggles to grasp Carol's rejection of such customs and her insistence that her brother Ryan holds no romantic significance.

Carol's compassion, intelligence, and integrity catalyze Memphis's transformation, softening his demeanor organically despite her initial view of him as irredeemably brutish. This profound personal growth culminates in genuine love and marriage. While his intense jealousy diminishes post-marriage, fierce protectiveness toward Carol persists. Memphis governs Egypt amid turmoil, facing threats from empires like Assyria, Babylonia, and the Hittites. Rulers such as Emperor Algon of Assyria and Prince Ismir of the Hittites specifically target Carol, coveted for her beauty, strategic value as the "Daughter of the Nile," and influence over Memphis. These external conflicts merge with romantic rivalries, compelling Memphis to navigate warfare and intricate court intrigues to safeguard his kingdom and queen.

Throughout, Memphis depends on loyal advisors, Prime Minister Imhotep and General Minue. His leadership evolves from capricious tyranny toward a more measured approach, significantly influenced by Carol's historical knowledge and diplomatic insights. However, his deep-seated stubbornness endures, particularly concerning cultural clashes with Carol and any threats to their union.