Neverwhere / Gaiman, Neil

Richard Mayhew's life is forever changed after he rescues a young girl named Door and finds himself living in a city of monsters, saints, murderers, and angels, and he must help Door on her mission to save this strange underworld kingdom from destruction.

Richard Mayhew, a young businessman living in London, helps an injured girl and finds his life changed when he leaves reality and enters the city's underground world of sewers and abandoned subway stations--a world in which the girl he helped is someone of power and nobility.

Richard Mayhew, a young businessman living in London, helps an injured girl and finds his life changed when he leaves reality and enters the city's underground world of sewers and abandoned subway stations--a world in which the girl he helped is someone of power and nobility.