Adonis was a youth of such extraordinary beauty that he was adored by Aphrodite. When he was but a child she hid him inside a chest which she left in the care of Persephone, goddess of the underworld. But Persephone disobeyed Aphrodite and opened the chest. Seeing Adonis, she too fell in love with him. When Aphrodite came to fetch the young man, persephone refused to release him.
The warring goddesses ended their dispute when Zeus decreed that Adonis would spend half of the year with Aphrodite and half of the year in the underworld with Persephone.
But Ares, the god of war, was jealous of Aphrodite and her passion for Adonis. He transformed himself into a boar, waited for the young man to go hunting, and fatally gored him, leaving Aphrodite to bitterly mourn her lost love.