Which English phrase, inspired by Pandora’s myth, describes an action that creates many unforeseen problems?

The phrase “opening Pandora’s box” describes an action that releases many unforeseen problems. It comes directly from the myth in which Pandora opens a container and troubles escape into the world.

In modern English, the expression is usually used metaphorically. A person may “open Pandora’s box” by starting an investigation, revealing hidden information, or making a decision whose consequences are difficult to control. The phrase emphasizes that one action can unleash a chain of complications.

The expression is related to the older mythological story, but its wording reflects later tradition. Hesiod’s original container was a pithos, or large jar, not a box. Even so, the box version became dominant in English and remains the basis of the idiom.

The phrase is often confused with “opening a can of worms.” Both suggest unexpected trouble, but “Pandora’s box” specifically invokes the Greek myth and usually suggests a broad set of harmful consequences rather than one messy problem.