Zeus was angry that Prometheous stole fire from heaven and gave it to his human creations.  Besides punishing Prometheous, Zeus had Hephaistos, the god of metalwork create a Pandora, who was both beautiful and foolish.

Zeus sent her to earth carrying a box, which she was ordered never to open.  The men were enchanted by Pandora and took her in.  Zeus knew Pandora could not resist the temptation to open the box.  When she did all the miseries that affect mankind flew out - war, famine, evil, sickness, and sin. Only hope remained in the corner of the box.