The book explores how Medusa embodies both protective and destructive forces, serving as a guardian figure while simultaneously being a source of terror. Her image was often used on ancient shields and doorways as an apotropaic symbol, highlighting the complex nature of her mythological role.

Lewis examines how Medusa's story reflects ancient Greek attitudes toward female power and sexuality, analyzing her transformation as a commentary on patriarchal authority and divine retribution. The text explores various interpretations of her curse and its implications for gender dynamics in classical mythology.

The author traces how the Medusa myth has evolved across different cultures and time periods, from ancient Greek pottery to Renaissance art and modern media, demonstrating how each era has reinterpreted her story to reflect contemporary values and fears.