A collection of stories by mostly well-known authors, purportedly all detectives in urban fantasy stories. In actual fact, many of these stories are not set anywhere near cities, several have no magical or supernatural elements, and at least two are neither urban nor fantasy. So I'm not actually sure what selection criteria GRR Martin was using. I don't feel like I wasted my time reading this, but I also don't feel particularly satisfied. I really liked seeing more of Kyle and Warren in Briggs's "In Red, with Pearls", although too many of the clues were unstated so that the mystery's end could be surprising. My favorite of this collection was Hanover's "The difference between a puzzle and a mystery," which was creepy but somehow also comforting.