Instruct: Classify a given review as either positive or negative.
Query: Interesting and Exciting

Starting with the first Alex Delaware novel "When the Bough Breaks", I have read all of his thrillers in chronological order, enjoying the Delaware character development as well as the individual stories (the same applies to Stephen White's equally brilliant Alan Gregory books, by the way).I still consider "Devil's Waltz" to be the best effort in a very good series of novels - believeable characters, interesting storylines and lots of mystery are always guaranteed when starting a Kellerman novel, but "Devil's Waltz" is the one I remember as especially tight and exciting. This book about damage inflicted on a helpless child and layer after layer of secrets within an L.A. hospital will keep you guessing right up to the final pages and is absolutely flawless.