While the winds belch fire, Jupiter opens the mortal womb of his lover Semele with a thunderbolt and snatches forth the baby god Bacchus. His love for Semele had enraged his wife the goddess Juno, who swore to destroy her. Disguised as Semele's old nurse, Juno tricked Semele into asking Jupiter to come to her in all his splendor. Thus Jupiter's godly presence set Semele's frail human body on fire. After Giulio Romano completed this preparatory drawing, it was squared so that his assistants could copy it onto another surface. Inventories show that Giulio made a painting with a similar subject for the ducal palace in Mantua to celebrate the birth of a Gonzaga prince in 1533, the son of Giulio's patron Federico Gonzaga. He may have made this drawing as a study for another painting of the same subject, now in the Getty Museum.