Perseus's mother's father heard a prophecy saying that his grandson would kill him so he put Perseus and his mother in a wooden chest and put them in the sea where they came to an island and King Polydectes wanted to get ride of Perseus because he thought he would be a problem and he wanted to marrie Perseus's mother.
you shall not enter
this is were the evil king told him to go get Medusa's head because he wanted to get ride of Perseus
Perseus is trying to get the location of Medusa from the Graeae. He made them tell him by taking there eye
Pursues has entered the cave where medusa lived he used the shoes with the wings to get to her and he cut her head off and her baby pegasus came out of her head
he saves the beautiful princess and gets permission from her father for him to marrie her because he killed the sea serpent.
he returns home married and saves his mother and tells her he is married and his mother is happy and surpised