In the early Roman Republic, plebeian citizens revolt due to a famine. The people name Caius Martius, a patrician (aristocrat) and a famous soldier, as their chief enemy, since he despises the common people. An old, reputable Roman patrician named Menenius Agrippa tries to calm the people by telling them a fable about the belly. Just as the people are calming, Caius Martius arrives, curtly telling the common people what he thinks of them, and announcing that their wish has been granted: Junius Brutus and Sicinius Velutus have been named tribunes of the people.
News arrives that the Volscians, among them Martius’s chief enemy general Tullus Aufidius, are attacking Rome, so Martius and Roman general Cominius lead the Roman forces against the Volscians. While some soldiers run away, Martius fights valiantly in the battle, single handedly capturing the city of Corioles despite being unable to kill his rival. For his excellence in the battle, Caius Martius is given the new surname “Coriolanus.”
Back in Rome, Menenius and Coriolanus’s mother, Volumnia, begin preparing for his political campaign. Despite the fact that he is hated by the tribunes, they hope to make him Roman consul. They’re excited to hear he has been wounded again, as wounds can be used to convince the people of his worthiness. In front of the Roman Senate, Cominius uses masterful oration to tell of Coriolanus’s valiant deeds, and officially nominates him for consul.
As part of the tradition of becoming consul, Coriolanus must ask for the people’s voices and show them his wounds. Though he is groomed by his mother, his general, and Menenius, Coriolanus is extremely hesitant to play politics. Coriolanus awkwardly asks the people for their voices, dressed in the traditional candidate’s robe, and they find it strange but agree. As soon as Coriolanus finishes, however, the tribunes are easily able to persuade the people to retract their votes by reminding them of how much Coriolanus hates them. The tribunes tell Coriolanus that the people have changed their minds, and he becomes enraged, berating the people for being fickle and continuing to espouse his view that they should be powerless. The tribunes take this to be treason, and they gather a mob of citizens to kill Coriolanus.
Ultimately, the tribunes agree to give Coriolanus a public trial, and Coriolanus’s supporters urge him to be calm and mild during the trial. Coriolanus doesn’t want to conceal his true feelings toward the people, however, and though he tries to do so at first, the tribunes are immediately able to enrage him, at which point he curses the common people publicly once more. The tribunes use this outburst as more evidence that he is the people’s enemy, and they sentence him to banishment.
Once banished, Coriolanus seeks out his rival Aufidius. At Aufidius’s house in Antium, Coriolanus reveals his desire to get revenge on Rome and asks if he can join with the Volscians. Aufidius and the Volscian lords agree, and the Volscian soldiers immediately become obsessed with Coriolanus. Aufidius, though, secretly plans to turn on Coriolanus once the Volscians have captured Rome. They lead a successful military campaign to the gates of Rome.
There, Cominius and Menenius come to the Volscian camp in attempts to dissuade Coriolanus from attacking his own city, but they are unable to do so. Coriolanus’s mother Volumnia, his wife Virgilia, their child young Martius, and their dear friend Valeria meet him outside the city in a final attempt to save Rome. By invoking their family bond, Volumnia is able to convince Coriolanus to abandon the military campaign, despite the fact that he knows this action might result in the loss of his life. Volumnia returns to Rome as a hero, and Coriolanus goes back to the Volscians, hoping they will accept peace between the two states.
In the city of Corioles, Coriolanus presents Volscian Lords with a formal peace agreement. Aufidius and his Volscian conspirators, however, tell the lords not to accept the agreement, calling Caius Martius a traitor to the Volscian state. Coriolanus becomes enraged, and Aufidius turns the Volscian people against Coriolanus by reminding them that he killed their families. At the protests of the Volscian lords, Aufidius and his conspirators kill Coriolanus.