Danae was the sole daughter of Acrisius, King of Argos and Eurydice of Sparta. Her maternal grandparents were Lacedaemon and Sparta, founders of the city of Sparta.
Acrisius worried about his successors and visited an oracle to learn if he would ever have male descendants. He was told that he would have a single grandson. But he would be killed by said grandson. Acrisius naturally wanted to avoid the birth of any such child. He had Danae transferred to an isolated cell, never to have any male companion. But Zeus had other plans. He gained entry to the cell in the form of a shower of golden rain. Impregnating Danae in the process.
Scared for his life but unwilling to slay his daughter by blade, Acrosius had the pregnant girl cast into the sea. Poseidon arranged for her safe passage to the island of Seriphos. Where Danae gave birth to Perseus. Mother and child were taken in by Dictys, a fisherman. He was an impoverished brother to Polydectes, King of Seriphos. Eventually Polydectes decided to claim Danae for himself. Wishing to dispose of Perseus, he send the boy to hunt Medusa.
Perseus returned with the head of Medusa. He petrified Polydectes and his nobles. Allowing Dictys to marry Danae and rise to the throne of Seriphos.