The common English expression is “open Pandora’s box.” It means to begin an action that releases many unexpected problems, complications, or harmful consequences.
The expression comes from the myth in which Pandora opens a sealed container and troubles spread into the human world. English speakers generally use it figuratively rather than referring to a literal box or to the full ancient story.
The phrase often describes decisions whose consequences are difficult to reverse. For example, a new policy, investigation, or technology may be said to open Pandora’s box if it produces a cascade of previously hidden issues.
A related expression is “let the genie out of the bottle,” but that phrase comes from a different tradition and does not refer to Pandora. “Open Pandora’s box” is also commonly written with an apostrophe because Pandora is the named owner of the container in the expression.