Shelley had travelled in the region of Geneva, Switzerland, where much of the story takes place. Ideas about occultism were topics of conversation among her travelling companions, especially her future husband, Percy Bysshe Shelley. Mary, Percy, Lord Byron, and his doctor 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 the result. She then wrote "Frankenstein".