In this one, I play a bit with Marquis backstory, ditto for Hunter, and have the crew run afoul of the Oxford Circus and its mysterious Ringmistress.
The Beginning Is the End Is the Beginning (19634 words) by Sophia_Prester
Fandom: Neverwhere - Neil Gaiman
Rating: Teen And Up Audiences
Warning: No Archive Warnings Apply
Characters: Richard Mayhew, Marquis de Carabas (Neverwhere), Door (Neverwhere), Hunter (Neverwhere), Serpentine (Neverwhere)
Some stories have many beginnings and many endings, and it can difficult to tell one from the other.
What can be said is that in the middle of this particular story, Door learns that finding her sister is not the same thing as getting her back, Richard struggles to come to terms with his new calling, and the Marquis may have forgotten something very important.