While in the first we still meet again some blood, violence in the discovery of the murders in the way the killer had to sign his murders here is too trendy psychology. It is far from a disaster, do not worry. It is genuinely interesting, but for my taste, too much patina.
If you liked the Whisperer, you need to read it because it represents the extension of the first. However, I am not convinced that I would begin the first volume in order to play the second ... Three stars for a book that has however a remarkable coverage and an interesting literary style.