Frankenstein; or, The Modern Prometheus is a novel written by Mary Shelley about a creature produced by an unorthodox scientific experiment. Shelley started writing the story when she was eighteen, and the novel was published when she was twenty-one. The first edition was published anonymously in London in 1818. Shelley's name appears on the second edition, published in France in 1823. The storyline emerged from a dream. Mary, Percy, Lord Byron, and John Polidori decided to have a competition to see who could write the best horror story. After thinking for weeks about what her possible storyline could be, Shelley dreamt about a scientist who created life and was horrified by what he had made. She then wrote Frankenstein. Mary Shelley (30 August 1797 - 1 February 1851) was an English novelist, short story writer, dramatist, essayist, biographer, and travel writer, best known for her Gothic novel Frankenstein: or, The Modern Prometheus (1818). She also edited and promoted the works of her husband, the Romantic poet and philosopher Percy Bysshe Shelley.