Let's add a bit to the topic..
Opening the Pandora's box means triggering events that are unexpected and usually bad..
"No sooner had Pandora opened the box, that she realized her mistake. A foul smell filled the air and she heard swarming and rustling inside. In horror she slammed the lid shut, but alas it was too late! The evil had been unleashed!
You see, the vindictive gods had each put something harmful inside the box. All the plagues and sorrows known to humanity were released once Pandora opened the jar. Old Age, Sickness, Insanity, Pestilence, Vice, Passion, Greed, Crime, Death, Theft, Lies, Jealousy, Famine, the list went on and on...every evil, that until then had been trapped inside the gift from the gods, was now loosed upon the earth."
Take a look here and pay attention to what was left in the box:
The myth of Pandora