Neverwhere

Neverwhere is the companion novelisation written by English author Neil Gaiman of the television serial Neverwhere, by Gaiman and Lenny Henry. The plot and characters are exactly the same as in the series, with the exception that the novel form allowed Gaiman to expand and elaborate on certain elements of the story and restore changes made in the televised version from his original plans. The novel enjoyed great success, whereas its television roots did not receive as much international exposure as the novel.
Plot
Neverwhere is the story of Richard Mayhew and his trials and tribulations in London. At the start of the story, he is a young businessman, recently moved from Scotland and with a normal life ahead. This breaks, however, when he stops to help a mysterious young girl who appears before him, bleeding and weakened, as he walks with his fiancée to dinner to meet her influential boss.
The morning after Richard rescued the girl, named Door, from the streets, she is greatly recovered, and sends him to find the Marquis de Carabas, a man who will be able to help Door escape two infamous and seemingly inhuman assassins, Croup and Vandemar. Richard brings the Marquis back to his apartment to meet Door, only to see both of them vanish immediately. Soon after, Richard begins to realise the consequences of his actions. He appears to have become invisible; he loses his job, where no one seems to recognise him, and his apartment is rented out to other people. His fiancée no longer recognizes him.
Determined to set things right, Richard tries to enter the world of London Below in search of Door. He finds a tramp from Below, who is the only person able to see him, and recites the name of the Floating Market as the only place known to him in underworld. The tramp brings Richard to the realm of the Rat-Speakers, who worship and perform tasks for rats. They attempt to assault and rob Richard, but follow orders from the master rat and let him free. He then travels across the mysteri