What is the standard English idiom for unleashing hidden troubles, inspired by Pandora’s myth?

The standard English idiom for unleashing hidden troubles is “open Pandora’s box.” It comes from the myth in which Pandora opens a sealed container and releases evils or hardships into the human world.

In modern English, the expression describes an action that creates many unexpected problems or consequences. It can apply to politics, technology, family disputes, legal cases, or any situation where investigating one issue exposes a much larger set of difficulties. The idiom usually emphasizes consequences that are difficult to reverse.

The expression does not normally refer to one specific physical box. It is figurative language based on the myth, and the “box” itself reflects a long-standing translation tradition. Hesiod’s original Greek account describes a pithos, a large storage jar.

“Open Pandora’s box” is sometimes shortened to “Pandora’s box,” but the full verb phrase is the conventional idiom for starting the chain of trouble.