Argus Panoptes or Argos is a many-eyed giant in Greek mythology. The monstrous entity has been either directly included or indirectly alluded to in a wide variety of works influenced by Greco-Roman thought over the past several centuries.

Argus Panoptes was a primordial giant whose epithet, "Panoptes", "all-seeing", led to his being described with multiple, often one hundred, eyes. Argus was Hera's servant. His great service to the Olympian pantheon was to slay the chthonic serpent-legged monster Echidna as she slept in her cave. Hera's defining task for Argus was to guard the white heifer Io from Zeus, who was attracted to her, keeping her chained to the sacred olive tree at the Argive Heraion.

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