In Hesiod’s Greek myth of Pandora, evils escaped from her container after she opened it. Works and Days says that the container held destructive troubles that had previously been absent from human life.
Hesiod describes diseases and countless other hardships spreading after the lid was removed. The story is therefore an etiological myth: it gives a legendary explanation for why suffering exists in the human world. Pandora does not release a single named monster or spirit; the text refers collectively to evils.
Hope remains inside when Pandora closes the container. Later traditions and translations often describe the surviving occupant as hope, producing the familiar expression “hope remains.” Scholars have debated the precise meaning and role of elpis, the Greek word involved.
The phrase “Pandora’s box” is also slightly misleading historically. Hesiod’s vessel was a pithos, a large jar, and the box wording became standard through later translation and retelling.