Mithridates, the Pontine king who was fighting the Romans for forty years, is defeated and believed dead. Xiphares, the son who is, like his father, an enemy of Rome, deplores sincerely the loss of Mithridates. The other son, Pharnace, favorable to the Romans, is all the more pleased because he is in love with Monime, the old king’s betrothed; now he hopes to win her for himself.
Xiphares tells Arbate that he, Xiphares, has no claims to the states Pharnace is to inherit and that his brother’s feelings toward the Romans are of little interest to him. His concern for Monime is another matter. The truth is that Xiphares himself was long in love with Monime, even before his father saw her. Although he remains silent as long as she is betrothed to his father, he is now convinced that Pharnace will be compelled to kill him in order to have her.
When Monime begs Xiphares to protect her against Pharnace, whom she does not love, Xiphares finally declares his love to her. At first he is afraid that she might receive his avowal with anger. Monime, however, is secretly in love with Xiphares. They do not open their hearts to each other because Pharnace appears. Pharnace urges Monime to support his cause in Pontus. She thanks him but explains that she cannot favor a friend of the Romans who killed her father. When Pharnace hints that another interest is prompting her, Xiphares confirms his suspicions by defending Monime’s freedom. The brothers then realize that they are rivals.
At that moment Phoedime, Monime’s confidant, arrives to tell them that the report of Mithridates’ death is false and that the king is returning. Monime and Xiphares, each sensing at last the other’s feelings, are stunned. Monime deliberately bids them farewell and leaves. Now Pharnace knows that Monime and Xiphares love each other, and Xiphares knows that Pharnace loves Monime and is expecting the arrival of the Romans. Both, afraid of their father’s anger, will be forced to keep each other’s secret when they meet him.
After everyone goes to meet Mithridates at the harbor, Phoedime is surprised to find Monime still in the palace. Monime explains her realization that Xiphares suffered as much as she did all the time they were separated after their first meeting in Greece. Aware that she betrays her love without even speaking, she feels that she can never see Xiphares again because she also fears Mithridates’...
(The entire section is 995 words.)