Lulling the Hundred-Eyed Watchman: Hermes and the Rescue of Io

Hermes's first day of life already included the cattle theft from Apollo and the invention of the lyre. A later episode, told most fully in Ovid's Metamorphoses, shows the grown god sent on a harder errand by his father Zeus. Zeus has transformed his lover Io into a heifer to hide her from jealous Hera, who is not fooled and sets the giant Argus Panoptes, covered in a hundred eyes of which only some ever sleep at once, to guard her. Zeus sends Hermes to free her, and Hermes approaches disguised as a wandering shepherd, playing a set of reed pipes and telling a long, deliberately tedious story about the nymph Syrinx until Argus's eyes close one by one. Once every eye has finally shut, Hermes kills the sleeping giant and leads Io away, though Hera then sends a gadfly to torment the still-transformed Io on a long wandering exile across the earth before she is finally restored to human form. Hera, discovering her watchman dead, takes his hundred eyes and sets them into the tail of the peacock, her own sacred bird, as a permanent memorial. Homer and later poets remember the killing directly in one of Hermes's own standing epithets, Argeiphontes, Argus-slayer, attached to his name across the Iliad and the Odyssey long before Ovid ever wrote the story out in full, evidence that the episode was old and well known rather than a Roman-era invention.