After a great battle, Julius Caesar has followed his foe, Pompey, into Egypt. In an ill-thought attempt to please Ceasar, the Egyptians murder Pompey to the horror of Pompey's wife, Cornelia, and his son, Sextus. Meanwhile, Cleopatra decides to use her beauty to seduce Ceasar to help defeat her brother, Ptolemaus. After Ceasar pledges his loyalty to Cleopatra, Sextus challenges Ptolemaus to a duel in order to avenge the memory of his father. When Sextus kills Ptolemaus, Cleopatra becomes the Queen of Egypt.