Medusa

Medusa was one of three Gorgons that arrived on Earth during humanity's early history.

She was the best known of the three and was often depicted as being a beautiful woman with snakes for hair. Like all Gorgons, she was noted for having the power to turn anyone who looked at her to stone. She was killed by the Greek hero Perseus. Her companions were later killed by Professor Edgar Nelson-Stanley and Sarah Jane Smith's team, respectively. (TV: Eye of the Gorgon)

The Second Doctor and Zoe encountered Medusa in the Land of Fiction. This was a fictional construct based on the legends surrounding the real Medusa. (TV: The Mind Robber)