Cicero has been elected President of the Roman State, leaving his opponent Catiline vowing revenge. Julius Caesar, a young senator, disagrees with Cicero’s Republican values, and plots to reform the old corrupt constitution. Caesar plans to bribe the electorate, attempting to lure Cicero into his plot.
Meanwhile, Catiline stands for Consul again, going against Clodius’ ally Murena, who is under Cicero’s guidance. Caitline plots a violent attack. Cicero discovers the plot, but can’t prove it until Crassus (who previously supported Caitline) gives him the evidence. This evidence is ultimately overturned. Rufus, Cicero’s young protégé, warns him that Catiline’s men are coming to kill him. When the conspirators are interrogated, Caesar is implicated in the plot. Cicero reluctantly passes death sentences on some of Rome’s leading citizens, but spares Caesar.
Following Cicero’s year as Consul, Clodius commits an act of sacrilege during a women’s festival, and the Vestal Virgins demand that he be publicly beaten to death. Cicero refuses to defend his young friend in court. Clodius’ sister pleads with Cicero but still he refuses to get involved. The jury is bribed, Clodius is acquitted, and swears revenge.
Pompey, Rome’s most successful military commander, returns to Rome demanding that his soldiers, and Rome’s poor, are given land.
When Hybrida, Cicero’s drunken consular colleague, is prosecuted for treason and corruption, Cicero is forced to defend him. Rufus, Cicero’s young pupil, uses the trial to attack his old master. Cicero publicly accuses Caesar of being the fountainhead of all the evils in the state. With Caesar’s scheming, Clodius resigns his aristocratic title, becomes a plebeian, and wins an election as Tribune of the People. Clodius’ street gangs now rule Rome. Caesar becomes Consul by a unanimous vote. Cicero, almost friendless, is forced to ask for Caesar’s protection.