Fig. to uncover a lot of unsuspected problems. When I asked Jane about her problems, I didn't know I had opened Pandora's box.You should be cautious with people who are upset. You don't want to open Pandora's box.
to start something that causes many new and unexpected problems They worry that any decision they make about testing will open a Pandora's box.What kind of Pandora's box do we open if we decide not arrest people who have committed a crime?
Etymology: based on an old Greek story in which a woman named Pandora opened a box containing all the troubles the world has experienced