Perseus is the son of Zeus and Danae (mortal daughter of King Acrisius...King of Argos). Unfortunately, the King had heard of a prophecy that this boy would kill him and so he locked the child and the mother in a trunk and threw them into the sea. They did not drown, but rather ended up adrift on the island of Seriphus where Perseus grew to be a young man. The King of Seriphus (Polydectes) wanted to marry Danae, but thought that Perseus would get in the way, so he sends him on a royal quest to take the head of Medusa.
In order to do this he knew he would need help so the enlisted the aid of Hermes (messenger of the gods) who took him to the Fates (they all have one eyeball between them). Perseus steals the eye and refuses to return it until they tell him where the nymphs are. He finds the nyphs who give him winged sandals, a magic wallet (which would fit whatever was put into it), and a cap to make him invisible. Hermes, himself, gifts Perseus with a sword that would never break, and Athena gets in on the act by giving him a shield (he later uses this to look at Medusa so he won't turn to stone).
Thus fortified, he goes off and kills Medusa. Medusa's sisters were not happy about that, but Perseus escapes by putting on his cap of invisibility and leaving the area by putting on his magic sandals and placing Medusa's head into the magic wallet.
On his way home he stops to rescue Andromeda (damsel in distress), battles a sea monster, and gets married. Back on the island Perseus uses Medusa's head to free his mother and turn the lusty King into a statue. Both Perseus and his mother have had enough and Perseus, his new wife, and Danae go back to Argos, where the prophecy is fulfilled (he kills the King).
