Pandora's jar.

PANDORA was the very first woman who was formed out of clay by the gods. The Titan Prometheus had originally been assigned with the task of creating man. But because he was displeased with their lot, stole fire from heaven. Zeus was angered, and commanded Hephaistos and the other gods to create a woman, Pandora, and endow her with the beauty and cunning. He then delivered her to Epimetheus for a bride. When he had received her into his house, Pandora opened the pithos (storage jar) which Zeus had given her as a wedding present, and released the swarm of evil spirits trapped within. They would ever afterwards plague mankind.

Only Elpis (Hope) remained behind, a single blessing to succor mankind in their suffering.

"...........Only Hope was left within her unbreakable house,
she remained under the lip of the jar, and did not
fly away. Before [she could], Pandora replaced the
lid of the jar. This was the will of aegis-bearing
Zeus the Cloudgatherer.........."