Richard Mayhew was a nobody.
He worked a dead-end job in London and his fiancé walked all over him. Everyone walked all over him.
Door was the daughter of an aristocrat from a mysterious parallel world beneath London. She had the ability to create and open portals to wherever she wanted to go.
One day, Richard encountered Door, bleeding and bruised lying in a London alley. To the frustration of his fiancée, Richard decided to take her to his flat to keep her safe and to heal. This act of kindness set in motion the events that overturned Richard's life. Soon, 2 cutthroat thugs came looking for Door and threatening Richard. The next day, everyone in Richard's life had forgotten that he ever existed. Before long, his work desk was moved and his apartment was rented to strangers.
Hoping to regain his life, Richard followed Door into London Below - a mysterious world, invisible to most Londoners and populated by the outcasts of the city above. he found Door and helped her on her quest, while evading the cutthroats on their trail. Along the way they encountered a fallen angel, a trained assassin, an invisible roaming marketplace, a haunted bridge draped in inky, deadly blackness, and a host of unusual characters.
In Neverwhere, Neil Gaiman builds a believable world of rejects and outcasts and makes them sympathetic to the reader. The story moves quickly and easily from mystery to action. The characters are rich and quirky and interesting - at times ridiculous; at times, terrifying. Gaiman's narrative is full of wit, while continuing to advance the story.
The reader feels the pain of Richard as he moves from being figuratively lost in the "real" world of London to being literally lost in the mysterious London Below.
Fans of clever writing and adventure stories will enjoy Neverwhere.