Danae is depicted here locked away from the reach of all men by her father -- well, almost -- and down from the roof comes Zeus in the shower of gold.
In Greek myth, Danae was the royal daughter of Acrisius, an ancient king of Argos. After an oracle warned her father that Danae's son would someday kill him, Acrisius had his daughter shut up inside a sealed room, atop an impenetrable bronze tower, away from all men. However, Zeus -- the amorous and all-powerful king of gods -- desired Danae. He came to her through the roof of the sealed chamber, in the form of a shower of gold that poured down into her lap. As a result of this union, Danae had a son -- Perseus -- the hero who later took on the chilling Medusa.
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Cellini's Perseus Beheading Medusa.