Hex and the City - Nightside, Bk 4 Author:Simon R. Green Lady Luck has hired John Taylor to investigate the origins of the Nightside--the dark heart of London where it's always 3 A.M. But when he starts to uncover facts about his long-vanished mother, the Nightside--and all of existence-- could be snuffed out.
Fourth in the series. Getting predictable now, the main character spends a lot of time trying to get answers from people who don't want to tell him anything, overall: still worth reading.