Neil Gaiman's Neverwhere by M. R. Carey

In a world hidden beneath the bustling streets of London, an ordinary man named Richard Mayhew finds himself thrust into a shadowy realm known as London Below after a chance encounter with a mysterious girl named Door. As he navigates this dark and dangerous underworld, Richard encounters a host of peculiar characters, including the enigmatic Marquis de Carabas and the deadly assassins Mr. Croup and Mr. Vandemar. Alongside Door, he embarks on a perilous quest to uncover the truth behind her family's murder, ultimately discovering his own courage and the power of choice in a place where the rules of reality are twisted and nothing is as it seems.

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