- “Back for more, you buzzard? Well, the chains are off this time!”
- ―Prometheus to the eagle after he landed in front of him and Hercules
Long ago, Prometheus decided to help humanity by giving then the gift of fire. In order to do this, he sneaked into Mount Olympus and used a torch to steal some fire from the sun. With this gift, humanity was able to excel and improve society. However, Zeus was angered by Prometheus for having disobeyed his rule about intervening in mortal affairs and for potentially endangering them by providing fire, so he punished the Titan by chaining him to a mountain in Tartarus, where a giant eagle (whom he will grow to develop a frenemy relationship with) would come each day to feast on his liver. Luckily (and possibly painfully), his liver would grow back after each night. Despite everything, humanity still remembered his noble act, and in his honor, they erected and named a school after him and a statue.
In Disney adaptation, his torments are designed to be comical in nature to make it family friendly. Instead of screaming in extreme agony due to the Eagle feasting on his liver, he simply yelled in irritation as though he is being bitten by bugs, and even has funny conversations with the Eagle.
During a Liver Thursday at Prometheus Academy, Hercules hears of the injustice Prometheus suffered, and decides to save him. Thus Hercules rescued Prometheus from the eagle. Learning that Hercules was unaware that Zeus imprisoned him, Prometheus omitted this fact. As they hid from the searching Olympians, Prometheus taught Hercules how fire required air to burn.
The next morning, the pair were discovered by the Olympians and Prometheus' omission came out as Hercules learns that his father was the one who punished the Titan and Zeus felt humiliated by his son for freeing him. Zeus attempted to justify his decision by saying that mortals weren't ready to handle fire, insisting it could've been a disaster. Hercules reasoned that humanity didn't destroy themselves, though he acknowledged that a few got burnt, Prometheus reminded that he taught them, "stop, drop and roll". But before Hercules could convince Zeus to forgive Prometheus, Hades, eager to undermine Zeus' authority, reminded that both Prometheus and Hercules defied him and suggested resolving the situation by a literal trial-by-fire. Though Hera protested involving Hercules, Zeus consented to the trial by fire. Hades then empowered the eagle into a fire bird, making the latter ecstatic to enjoy fried liver. Hercules, recalling Prometheus' advice about fire requiring air to burn, ripped off the Titan's toga, revealing he had a diaper underneath, to Prometheus' amazement, and smothered the eagle, reducing him to a normal giant bird. Afterwards, Hercules got Zeus to apologize to Prometheus, who felt relieved that the King of Gods admitted he was wrong.
Prometheus later went to Prometheus Academy to address the student body. After requesting that the eagle on his statue be removed, he stated how he was always sympathetic to humanity and he had considered what to do for an encore that brought joy to all but Icarus: no more Liver Thursdays.
Prometheus does not appear on the show. However, his flame is used by Merlin to convert the Graal in the sword Excalibur. Later, the same flame is used by the new Dark One Emma Swan to reunite the sword with the Dark One's dagger.