One day Io, the daughter of the river god Inachus, inadvertently attracted the attention of Zeus as she was busy performing her priestess duties in the temple of Hera.
Each night as Io lay sleeping, the god would appear in her dreams and invite the maiden to come and meet with him in a nearby meadow. Alarmed by these nightly rendezvous, Io voiced her concerns to Inachus who promptly dispatched a messenger to seek advice from the Delphic Oracle.
When the herald returned from his inquiry, he brought with him a somber message. Apollo’s priestess warned Inachus to permanently exile Io from her homeland lest the city of Argos would be destroyed by a thunderbolt. Sadly, Inachus had no other option but to banish Io from her home.
It came to be that one day Hera, who was unable to locate her husband anywhere on Mount Olympus, looked down and saw that the earth was tightly wrapped in a mysterious thick black mist.
Immediately suspecting that Zeus was behind the odd occurrence, the suspicious goddess sped down from the heavens to investigate. Hearing the sound of approaching footsteps, Zeus, who was hiding Io amongst the veil of fog, quickly changed his paramour into a snow white heifer.
When Hera parted the vaporous haze, she found her quizzical husband sitting alone with only a beautiful white cow for company. Convinced that there must be more to the story, Hera slyly requested that Zeus award her the fine looking animal as a gift.
Because he did not want to draw any more attention to himself, the defeated god sighed and quietly handed Io over to his wife.
Hera then demanded that Argus Panoptes, a giant whose body was covered with one hundred eyes stand guard over the unfortunate maiden. No where in Greece could one find a better watchman, for Argus never closed all of his eyes at the same time.
Io was taken to the Groves of Mycenae, where she was tied to an olive tree and staunchly observed, both day and night. Zeus sent his messenger Hermes to steal the cow away, but even the god of thieves found it impossible to avoid the vigilant stare of Argus.
Fortunately for Io, Hermes was also the god of trickery, and it did not take him long to devise a plan for restoring her freedom. The god clothed himself in the robes of a shepherd and approached Argus while playing a tune on a homemade pipe of reeds.
The giant found the music to be very pleasant and readily invited the unfamiliar minstrel to join him in the grove. Hermes sat down on a rock and continued playing, occasionally pausing to tell long winded tales of satyrs and other woodland deities.
As the god moved on from one story to another, he noticed that the eyes of the giant were beginning to become very heavy with slumber. He watched as one by one they closed, until finally Argus was fast asleep. Hermes then jumped to his feet and swiftly killed him with his pointed sword
Hera was so distraught over the death of her faithful servant, that she removed his eyes and placed them on the tail of her favorite bird, the peacock. She then turned her wrath onto Io and sent a monstrous gadfly to torment her with its constant sting.
In her anguish, Io crossed through many lands trying to escape the winged devil that pursued her. As she entered into the heart of the Caucasus Mountains, she came upon the spot where the imprisoned Prometheus lay bound.
The titan kindly offered his help by pointing out the best route for the heifer to follow. Frightened and confused, Io continued onward frantically running along the shore in search of a safe place to catch her breath.
Lacking the strength to move on, Io finally came to rest upon the banks of the Nile River. As she refreshed herself in the cool water, Zeus suddenly appeared and restored her back to human form.
The two resumed their love affair and in due time Io gave birth to a son named Epaphus. When the time came for Zeus to return home to his wife, he arranged for Io to marry King Telegonus of Egypt.
Epaphus grew to manhood in the home of his stepfather and eventually inherited his crown. Epaphus is credited with founding the city of Memphis and his descendants with colonizing the cities of Thebes, Crete and Argos.