Perseus is the son of Danae, Princess of Argos, and the god Zeus. When hi is very young, his mother moves with him to live on the island of Seriphos.
Later, Polydectes - the king there - wants to marry Danae. Perseus says 'no' to this, so Polydectes sends the young man away for the head of Medusa - a she-monster, with snakes for hair. Can Perseus find and kill Medusa? And what happens after he goes back to Seriphos?