I find it very hard to fault this book because to me this was utterly delightful. The book is set in a post-apocalyptic zombie world where survivors have herded strange children who technically are zombies ("hungries" as they're called) but have brain capacity to think, speak and act human. We open with a POV of our main character, Melanie, a girl about age 9 who is one of these special children and each morning she gets wheeled at gun-point to her classroom where her adored teacher, Ms. Justineau, teaches them all sorts of wonderful things. Ms. Justineau sees them as children despite the decease that lives within their bodies but these children are property of Dr. Caldwell who is determined to find a cure to the decease that has ravaged the human population. Our 3rd main character, who became such a great character by the end, was Sergeant. He is the head of security of the base and he sees the children as monsters. He's a true military man who keeps his eye on survival the entire time. 
 Our plot thickens and explodes from there. There are some seriously disgusting scenes in this book but I can handle horror much better in book form than film form so I was OK with all the gory details and the nearly sadistic fervor that Dr. Caldwell has. 
 This is a character-driven novel that follows the psyche of 4 adults and the 1 child. I gobbled this book up; in less than 2 days I had finished it while working a full time job so I can tell you it's a page turner. Carey left me incredibly impressed by her portrayal of humanity. None of these characters are perfect, quite often they are rather terrible but they are rich in humanity and I appreciated that. Melanie was such a gem of a character, her thought process, her devotion to Justineau, her childlike wonder at the world around her was some of my favorite things. 
 I also really loved the theory of the zombie apocalypse, it was interesting and though it did have moments filled with scientific explanations they were accessible and interesting. I highly recommend this book weather you're young or older; I think anyone can really enjoy this.