"A book that will shock the conscience of a nation" [Too Much Coffee Man]

The short text at the back of the book/cover that is usually a summary of what the book is about, I believe. Also often had some short reviews, like the op title refers to. (The stuff you look at when you are deciding if you want to read the book or not, generally.)

They're quotes from book reviews.
For example: "...an emotional rollercoaster!"