Prometheus is a Titan and a prophet who formerly aided Zeus in the war against the older gods. He functions as humanity's greatest benefactor, having stolen fire from the gods to prevent Zeus from destroying the human race. Bound to a remote cliff, he endures horrific physical torture but maintains complete control over his mind and his secrets. He stubbornly values his freedom of speech over physical comfort, refusing to submit to the new divine regime.

Io is the human daughter of Inachus, an Argive princess whose beauty attracted the unwanted lust of Zeus. Punished by a jealous Hera, she has been partially transformed into a cow and is driven madly across the earth by a biting gadfly. Exhausted and terrified, she seeks out Prometheus's prophetic abilities to learn when her wandering and suffering will finally end.

Zeus is the newly established ruler of the cosmos, having recently defeated the older generation of gods to seize control. He operates as a harsh, insecure, and deeply tyrannical king who invents his own arbitrary rules of justice. He demands absolute obedience from all beings, hoarding power and aggressively punishing anyone who threatens his supremacy or acts independently.

The Chorus is composed of the Oceanids, the daughters of the Titan Ocean and his wife Tethys. They serve as sympathetic witnesses to Prometheus's suffering, weeping at the sight of his cruel treatment. While they frequently criticize the harshness of Zeus's new rule, they also try to persuade Prometheus to stop speaking out, believing his rebellion is foolish and dangerous.

Hephaestus is the Greek god of the forge, specifically tasked by Zeus with binding Prometheus to the rock. He performs his duty with a heavy heart, viewing Prometheus as kin and openly pitying his brutal fate. Despite his compassion, his fear of Zeus overrides his morals, forcing him to act as an instrument of divine punishment against his will.

Ocean is a fellow Titan and the father of the Chorus. Unlike Prometheus, Ocean has accommodated himself to Zeus's new regime and adopts a pragmatic, compliant approach to power. He attempts to act as a mediator, advising Prometheus to swallow his pride and submit to the new king to avoid further torture.

Hermes is the official messenger of the gods and a fiercely loyal servant to Zeus's new administration. He embodies the ruthless, unyielding nature of the current regime. Tasked with interrogating Prometheus about a secret prophecy that threatens Zeus's reign, he relies on arrogant threats and promises of escalating violence to demand compliance.

Might is a personification of sheer force and a highly dedicated servant to Zeus. He takes cruel pleasure in enforcing the new king's tyrannical decrees. Completely devoid of pity, he mercilessly taunts both the captive Prometheus and the hesitant Hephaestus, ensuring the punishment is carried out to its absolute maximum severity.

Violence is a direct servant of Zeus and companion to Might. Together with his partner, Violence represents the brutal, uncompromising physical force that sustains Zeus's new regime and crushes all opposition.