Glaucus was fishing in the river, he hauled in his catch, and on emptying his net noticed the fish he had already caught were reviving, and escaping back into the water, wondering what was causing this to happen, he took a closer look and realized he had emptied his catch on a patch of strange herbs on the river bank. Glaucus picked a handful of these strange herbs, and on tasting them had an urge to enter the river, he plunged in, and no sooner had he entered the water he had changed into a sea-monster with sea-green hair, huge broad shoulders and a fish-like tail. His transformation was accepted by the gods, and so Glaucus became immortal, a sea-god
One day he spied a beautiful girl, Scylla, a favorite of the water-nymphs, and fell instantly in love with her. Scylla on seeing Glaucus ran away, and no matter how he tried she kept on rejecting him. Felling sorry for himself Glaucus went to the island of Aeaea to confide in Circe, she was a sorceress and had the power to cast spells. Glaucus told Circe of his love for Scylla and of her rejection for him, he also told Circe that he could never love anyone else except Scylla.
Circe, who was very fond of Glaucus felt angered by this, and made her way to the island of Sicily, where Scylla lived. While Scylla bathed in a small spring, the jealous Circe poured a potion of herbs into the water, then cast her spell. From the lower half of her body Scylla grew six monstrous dogs, but the upper half remained intact. Totally appalled by the appearance of her body she hid herself away in a grotto on the straits of Messina, and there she stayed, but she could not stop the monstrous dogs from devouring unsuspecting sailors who steered to close to her cave, and Glaucus continued to pursue Scylla but to no avail.