Kratus and Bia carry Prometheus to a mountain in the Caucasus. Hephaestus follows them. Kratus explains that this is where Prometheus must be chained to a rock on the orders of Zeus in punishment for giving fire to human beings. Prometheus is expected to learn to like Zeus and stop liking humans. Hephaestus, whose job it is to bind Prometheus to the mountain, groans that he finds it difficult to do this to a fellow god. He explains, however, that he has no choice but to obey Zeus. Prometheus must be punished for stealing fire from the gods and unjustly giving it to mortals. He will remain there for a long time because his liberator has not been born yet. Hephaestus mentions that Prometheus will be unable to soften Zeus's heart for a long time, since Zeus is harsh like all new rulers.
Kratus urges Hephaestus on, asking why Hephaestus does not hate the enemy of the gods. Hephaestus explains that friendship binds them, but Kratus replies that the word of Zeus should have the most weight. Hephaestus mourns that as the blacksmith he has been given this task and accuses Kratus of being heartless and ruthless. Kratus replies that the punishment has nothing to do with Hephaestus's talent as blacksmith, but that Prometheus alone brought it on himself. There is no point in pity or reluctance since the punishment must be carried out regardless. One should be afraid of disobeying Zeus, and questioning Zeus's orders is dangerous. Once Hephaestus has finished attaching the bonds, Kratus tells Prometheus that he was foolish to help mortals because now they cannot help him. Hephaestus, Kratus, and Bia leave.
Prometheus calls upon the forces of nature to witness his torture at the hands of his fellow gods, particularly at the hands of Zeus, the new ruler. Prometheus questions how long he will remain bound to the mountain, but quickly corrects himself, remembering that he already knows everything that will happen. Nothing that can happen will be new to him, so he must find the best way to deal with his fate since no one can fight against destiny. Prometheus again repeats what Hephaestus has already said: he is being punished for stealing fire from the gods and giving it to human beings, who have learned all the arts from it. Suddenly the sound of wings approaches, and Prometheus asks what this sound is, exclaiming that he fears everything that comes his way.
Kratus's name means "force" or "might" in ancient Greek, while Bia means "violence." Greek myth commonly personifies abstract concepts, as well as forces of nature, as gods. In Aeschylus's hands, however, the names are part of his wider poetic scheme. Zeus himself never appears, but is constantly referred to. Possibly there were restrictions on representing Zeus, greatest of the gods, as a character on stage. Zeus's absence and his replacement on stage by Force and Violence, add to the effect of the drama. Zeus governs the world from a distance and acts through his agents. The simple fact that his representatives are Force and Violence gives us an immediate intimation as to Zeus's character, as he rules only through brute force.
At first it seems a little odd that only two of the four characters on stage actually speak, especially since both of them address a silent Prometheus to no effect. This seems less odd if we realize that the simplicity of a two-way conversation greatly reduces clutter. Bia does not need to speak, since we may assume he would only echo the words of Kratus. Prometheus, although he is directly addressed, would only confuse the action by answering. Aeschylus clearly wants Zeus's servants to express their views of Prometheus before we hear the other side from Prometheus himself. Furthermore, since this is the prologue to the tragedy, Aeschylus wants to explain events as simply as possible, without introducing a third viewpoint when two are already being presented. Prometheus's own silence also serves as a sign of his resolution. No matter how strong his suffering, he will not speak to his oppressors. Besides telling us the reason for Prometheus's punishment, the first dialogue introduces us to an important distinction between Kratus and Hephaestus. While both must follow Zeus's orders, Hephaestus does so against his own will while Kratus carries out Zeus's orders without thinking. The two gods are archetypes of servants: the willing and the unwilling collaborators.
Aeschylus's uses the opening dialogues to clearly paint the scene of the action. Kratus refers to the area as "the world's limit an untrodden desolation." References are made to the high rocks, the hot sun, and the night cold. As soon as he speaks, Prometheus immediately invokes the surrounding elements: the ocean, the earth, the wind, and the sun. Both Hephaestus and Prometheus also mention the longs stretch of time for which Prometheus is to be confined to the rock. Greek tragic drama was distinguished by unity of place and time: the scene could not change, and the action had to take place all at once. Aeschylus uses these lines to expand the audience's perception of both the location and the time of action. Furthermore, both serve to underscore Prometheus's isolation. The human beings on whose behalf he is punished will not be able to see him so far away from all civilization. He is left completely alone with the elements.