Perseus In Greek mythology, the slayer of the Gorgon Medusa and the rescuer of Andromeda from a sea monster. Perseus was the son of Zeus and Danae, the daughter of Acrisius of Argos. Fearing the fulfillment of a prophecy that he would be killed by his grandson, Acrisius cast both Danae and the infant Perseus (imprisoned within a chest) into the sea. The vessel was washed up on the island of Seriphus, where Perseus spent his youth. King Polydectes of Seriphus, who desired Danae, tricked Perseus into promising to obtain the head of Medusa, the only mortal among the Gorgons.
Aided by Hermes and Athena, Perseus forced the Graiae, sisters of the Gorgons, to provide him with winged sandals (which enabled him to fly), the helmet of Hades (which conferred invisibility), a curved sword, or sickle, to decapitate Medusa, and a bag in which to conceal the head. Because the gaze of Medusa turned all who looked at her to stone, Perseus guided himself by her reflection in a shield given him by Athena and beheaded Medusa as she slept. He then returned to Seriphus and rescued his mother by using Medusa's head to turn Polydectes and his supporters to stone.
A further deed attributed to Perseus was his rescue of the princess Andromeda when he was on his way home with Medusa's head. Andromeda's mother, Cassiopeia (Cassiope), had claimed to be more beautiful than the sea nymphs, or Nereids, and Poseidon had punished the kingdom by flooding it and plaguing it with a sea monster. An oracle informed Andromeda's father, King Cepheus, that the ills would cease if he exposed Andromeda to the monster, which he did. Perseus, passing by, saw the princess and fell in love with her. He turned the sea monster to stone by showing it Medusa's head and afterward married Andromeda.
Later Perseus gave the Gorgon's head to Athena, who placed it on her shield, and gave his other accoutrements to Hermes. He accompanied his mother back to her native Argos in order to be reconciled with Acrisius, but Acrisius was not there when they arrived. Soon after this Perseus went to Larissa to compete in an athletic contest. Acrisius, who happened to be there as a spectator, was accidentally struck dead by a discus thrown by Perseus, who thus fulfilled the prophecy that he would kill his grandfather. He subsequently founded Mycenae as his capital, becoming the ancestor of the Perseids, including Heracles.