Thyestes is a Roman tragedy attributed to Seneca (4 BCE-65 CE), likely composed in the first half of the first century CE. Thyestes handles an episode from the myth of the brothers Thyestes and Atreus, who vied for the throne of Argos. The play details Atreus’s revenge against his brother, which involves tricking him into unwittingly eating his own children. Like many of Seneca’s tragedies, Thyestes drew on earlier Greek and Roman tragedies that dramatized the same myth, all of them now lost. The play explores themes of The Destructive Power of Desire, The Overturning of the Natural Order, and The Meaning and Nature of Power. Other plays by Seneca include Medea, Oedipus, and Phaedra.

This study guide uses Emily Wilson’s translation of the play from the Oxford World Classics volume of Seneca: Six Tragedies (2010).

Content Warning: The source material of this study guide features the death of children.

Plot Summary

The play’s first act shows the ghost of Tantalus arriving on stage. Tantalus, the sinful ancestor of the Argive king Atreus and his brother Thyestes, has been dragged up from the underworld by one of the Furies to infect the royal house of Argos with his evil frenzy. The Chorus enters and sings the first ode, beseeching the gods to put an end to the wickedness of Tantalus’s line. They reflect on the impiety of Tantalus and the terrible punishments he must now suffer in the underworld.

Act II begins with Atreus conferring with his Servant on the best way to take revenge on his brother Thyestes, with whom he has had a longstanding rivalry. The Servant urges Atreus to consider his reputation and to do the right thing, but Atreus does not listen to him. He devises a plan to make Thyestes eat his own sons after inviting him back to Argos for a sham reconciliation. In their second ode, the Chorus finds fault with conventional definitions of power, placing self-control over tyranny. They praise a life of simplicity and seclusion.

In Act III, Thyestes enters with his sons. He expresses hesitation about returning to Argos, not trusting his brother. Thyestes’s son (named as Tantalus or “Tantalus Junior” in most editions) convinces him to put aside his doubts. Atreus greets his brother and nephews lavishly. He even makes a show of presenting Thyestes with the crown. The Chorus sings the third ode. They are surprised at Atreus’s apparent warming toward his brother: No fortune, good or bad, goes on forever unchanged.

A Messenger bursts in, ushering in Act IV. He describes how Atreus sacrificed Thyestes’s children, cooked them, and served them as a meal to Thyestes. The Chorus is horrified. In their fourth ode, they note that the sun has turned back in its course and wonder if Atreus’s actions have violated the natural order so grievously that the world is now to be destroyed.

Act V begins with Thyestes taking pleasure in his feast, though he is still plagued by a dread he cannot fully understand. Atreus mocks Thyestes before finally revealing that he has fed Thyestes his children. Thyestes prays to the gods for revenge.