Book 3 of the Knights of Breton Court Trilogy. The entire trilogy was a "Meh" read. A very interesting concept, the King Arthur saga replayed in a modern day urban ghetto, hurt by the fact that the author chose to use the mystical/fantasy element of the King Arthur legend and poorly used them by not setting up a very plausible reason for mystical beings such as Merlin, Morgana Le Fay, the elemental Green Knight (known by the street name Green) & Mordred (street name Dred) choosing to live in the inner city ghetto of Indianapolis, Indiana of all places. Had the author told a real world urban take of this story, ala the Wire it would have be a far better read considering he does do a decent job of capturing the feel of life in an inner city ghetto.
The book series of Simon R. Green are only for the hardcore fans of sci-fi/fantasy/horror & comic books. Especially anyone into British sci-fi. Green's series are straight no holds barred action with over the top heroes & villains that would be at home in very dark cutting edge comic books. An just like comic books various characters, devices/artifacts & situations from one series have a tendency of crossing over into or being referenced in other series.
Green's Ghostfinders series is one part Ghostbusters, one part X-Files & on part Dr. Who spin-off series Torchwood, centering around the adventures of three operatives for the ultra classified British agency called the Carnacki Institute, an agency dedicated to investigating & handling paranormal activities, especially any that may pose a threat to humanity.
Green's Nightside series is a detective/horror/action series focusing on supernaturally gifted private investigator John Taylor and his adventures as the unofficial champion of the Nightside, a secret mystical city hidden at the heart of London that is home to humans, monsters, gods, demons & aliens for various timelines, dimensions & alternate realities and serves as a nexus point for all beings who know of it & are willing to pay a price to indulge in any of their darker & taboo vices /fantasies. And as the name implies, it's always night in the Nightside. There is never daylight. This is the twelth and final Nightside novel (but not the end of the adventures for the main characters) focusing on John Taylor's final case as a P.I. in the Nightside before marrying his now pregnant girlfriend & partner, the Nightside's most infamous bounty hunter "Shotgun" Suzie Shooter (she's the Bride of the book's title and woman on the cover) as well as his ascending to the position of "Walker" the enforcer and peace keeper for the Authorities, the powerful individuals who act as the guardians of the Nightside, a position that Taylor does not want but was forced to take after he killed the last "Walker". A man who was for most of his life both his guardian and mortal enemy.