This book reviews all the clues that are presented by JK Rowling in the first 4 Harry Potter books. It breaks the clues down as to specific for that book and/or related to the entire septology. The book also points out the connections between names and numbers to events and people. However, this book also leans more toward the UK versions of the book rather than the US version.
I liked the sections for each chapter where the action is paraphrased and then it is followed by the explanation of the clues. Then each chapter is summarized for oddities and questions raised.
This approach definitely makes you look at the books from a different point of view. However, I'm not sure that it really helps the appreciation of the story.