Scylla (Greek: Σκύλλα, transl. Skýlla), in Greek mythology, according to Homer and Ovid, was a beautiful nymph who turned into a sea monster.
According to the Roman poet Ovid, Glaucus was a human that the water divinities decided to transform into a sea creature, with a grayish-green beard, broad shoulders, blue arms, curved legs with fins at the end.
He falls in love with the nymph Scylla, who, terrified by his appearance, flees, through the waters, the rocks, the underwater caves. But poor Glaucus' love was immense, and in desperation, he sets out in pursuit of the beautiful nymph, begging her, in tears, to grant him a little attention.
Impassive to his pleas, Scylla continues her escape, hiding in a place so inaccessible that Glaucus could never find her. After a futile search, Glaucus is forced to acknowledge his defeat. Only some superior power would enable him to win the affection of the beautiful nymph.
Abated and tortured, Glaucus goes to the island of Aeia, where Circe, the sorceress, lived, and begs her to help him win his beloved. Circe promises to help him, but ends up falling in love with the sea god.
Since Glaucus rejects her, Circe is now the one who sets off relentlessly on a journey across the seas in search of her beloved. As a woman's charms prove insufficient, she resorts to her sorceress' powers, and decides to transform Scylla into a creature so hideous and repulsive that all of Glaucus' love would turn to loathing.
Unseen, Circe pours poison into the waters of a fountain where the nymph used to bathe and returns to the island of Ea where she awaits the results. When Scylla dives into the bewitched water her beautiful body slowly begins to transform.
Horrible monsters appear around her with deafening clamor. Terrified, the nymph tries to fend them off and escape. Then she discovers that the monsters are part of herself, born from her body.
Desperate, she runs to Glaucus and weeps longingly in his arms. He too laments his lost beauty, but refuses to remain with the ancient nymph, for the great love is no more.
Scylla retreats far away and goes to live in the Messina strait, between Sicily and the Italian peninsula, terrifying the mortals who previously courted her, dazzled by her extraordinary beauty.
On the island of Ea, Circe uselessly awaits Glaucus' return. Disgusted by her treachery and cruelty, Glaucus never wants to visit her, spending his entire existence cultivating the memory of a beautiful and sweet nymph, who one day got lost in the spells of jealousy.
The terrifying sea monster that Scylla was transformed into had the torso of a beautiful woman, but around its waist it had six serpent heads with three rows of teeth and a circle of twelve labrador dogs. The dogs would alert her when a ship was passing, so that she could capture the sailors.
Homer's version, in The Odyssey
According to Homer's Odyssey, for whom Scylla was the daughter of the river Scylla, when Odysseus' ship passed by the cave where Scylla was hiding, dogs jumped out and devoured six of his companions.
In Greek mythological tradition, Scylla was usually related to Caribdis, another sea monster. The two lived on opposite sides of the Strait of Messina and personified the dangers of sailing near rocks and eddies. On top of the cliff, which was not as high as the opposite cliff of Scylla, stood a black fig tree. Caribdis proper stood out of sight.
In other versions, Scylla was the daughter of Phocis and Hecate or even Lamia. As with most of the sea gods, she was sometimes also thought to be the daughter of Typhon and Echidna; Hyginus says she was killed by Hercules.