Medusa is the sole mortal in a family of gods. Growing up with her Gorgon sisters, she begins to realize that she is the only one who experiences change, the only one who can be hurt. And her mortal lifespan gives her an urgency that her family will never know.

When the sea god Poseidon commits an unforgivable act in the temple of Athene, the goddess takes her revenge where she can - and Medusa is changed forever. Writhing snakes replace her hair, and her gaze now turns any living creature to stone. The power cannot be controlled: Medusa can look at nothing without destroying it. She is condemned to a life of shadows and darkness.

Until Perseus embarks upon a quest to fetch the head of a Gorgon . . .