Oedipus is the King of Thebes, having claimed the throne after defeating the fearsome Sphinx. Tormented by a prophecy predicting he will kill his father and marry his mother, he lives in self-imposed exile from his homeland of Corinth. He is a conscientious ruler desperate to save his people from a deadly plague, though he suffers from deep-seated anxiety and paranoia regarding his own fate.

Jocasta is the Queen of Thebes and the widow of the former king, Laius. She is a proud, pragmatic royal who believes a leader should stand firm in the face of adversity rather than surrender to fear. She actively supports her husband's rule and dismisses his anxieties, viewing the city's current crisis as a chance for him to prove his strength.

Creon is a Theban royal, serving as a key advisor to Oedipus. He acts as a messenger between the crown and the divine oracles. Unlike ambitious politicians, he values the comforts of royalty without the heavy burdens of kingship and maintains loyalty to the throne, though his duties soon place him in a precarious position.

Tiresias is the revered blind prophet of Thebes. Though he lacks physical sight, he possesses the ability to read divine signs and uncover hidden truths. He relies on his daughter to describe the physical world during his complex rituals to summon answers for the royal family.

Manto is the sighted daughter of the prophet Tiresias. She serves as his eyes during rituals, observing and describing the physical signs of the sacrifices so her father can interpret their divine meaning.

Laius is the former ruler of Thebes who was killed on the road years before the play's current events. His unresolved murder is the source of the plague currently devastating the city, prompting a desperate search for his killer.

Old Corinthian is a messenger who travels to Thebes with important updates regarding the throne of Corinth. He holds key information about the past that he hopes will ease the current king's fears.

Phorbas is the chief herdsman of Thebes who once tended flocks on Mount Cithaeron. He holds hidden knowledge about a baby abandoned in the mountains years ago, making him a crucial witness in the investigation.

Polybus is the King of Corinth. He raised Oedipus as his own son, though his existence is the primary reason the young prince fled his homeland in fear of committing a grave sin.

Merope is the Queen of Corinth and the woman Oedipus believes to be his mother. Oedipus's intense fear of committing an incestuous sin against her keeps him in self-imposed exile.