In some ways, this is a stereo-typical noir parody. The detective, Eddie LaCrosse is an embittered cynic, just trying to get by and deal with his dark past. His office is above a bar people with tough characters and an even tougher barmaid. An old friend (who is now a pretty important guy) drops by with a problem -- it seems that his wife has gone crazy and killed their son. The friend wants Eddie to investigate and see if everything is as it seems to be (hint: it's not.) Eddie has to not only solve the mystery, but also confront some of the demons of his past.
Now take that story, and move it to a time of swords and horses. Eddie's friend is a king, and magic is involved in daily life. Eddie still has to solve the mystery, but now there are sword battles and curses and all the tropes of fantasy.
It's an odd cross between Sam Spade and Lord of the Rings, but it somehow works. The character of Eddie is great, and the mystery was intriguing. It's particularly entertaining for anyone who enjoys both of the parodied genres, but the author--while certainly working the parody angle--is serious about the plot and making the story work on its own. The details are great, and I often found myself chuckling aloud at the dialogue or at Eddie's take on how events unfold.
I really enjoyed this, and look forward to picking up the other books in the series.