The King of Argos had only one child, a daughter named Danae. Although beautiful, the king wanted a son and went to the Delphic oracle to ask if there was any hope of having a son. The oracle said “no” and worse that Danae would have a son who would kill him. The king could not put his innocent daughter to death so he built a room sunk underground but with part of the roof open to the sky so that light and air could come through.
As she lay there a mysterious thing happened. A shower of gold fell from the sky, it was Zeus in this form who impregnated her and she would bear the son who would kill her father the king.