The last two pages of Roses Are Red, the prior Alex Cross novel, reveal the identity of one of the bad guys in Violets Are Blue. Your enjoyment of Violets Are Blue will be vastly reduced if you know who did it in advance. If you decide to read that book, stop at page 398 and cover page 399 with a sheet of paper so you don't accidentally see any material on it. Then read this book. After that, go back and read pages 399 and 400 of Roses Are Red. Also, be careful which reviews you read of both of these books. Some reviews reveal this information as an ultimate spoiler, harming your enjoyment of two books.
"You're next, Dr. Cross." The hunter becomes the hunted in this unusual novel about finding mass murderers. How would you feel if your cell phone caller told you that you were the next person to be mutilated and murdered? That's part of the suspense of this book.
The main story line in Violets Are Blue is locating and stopping a murder spree being conducted by people who kill others so that they die from loss of blood. The way they lose this blood is not for the squeamish. Variations on this grossness are developed to be sure you get the maximum shock value. I found the story contrived, unrealistic, and unappealing. On the other hand, if you like old vampire movies, you may see this as high camp and a lot of fun. Who knows?
What Mr. Patterson does best is write plots, so with a weak plot here, there's not much good I can say about the book. It has the usual hard-to-differentiate characters, uninspiring dialogue, lack of any police procedure worth mentioning, and description of crime in mostly amoral terms.
Now, if Mr. Patterson were to write locked room mysteries, he would really be something. In his concept here of trying to describe being a metropolitan detective dealing with Stephen King figures, his talent just doesn't work.
If you really love Alex Cross books, go ahead and read this one. But remember that I warned you that you probably wouldn't like it! If you have read Roses Are Red, you will probably like this book much less. If you have read the last two pages of Roses Are Red, you may actually find this book annoying. I did. Be forewarned!
Where does providing too much, make something less? Certainly, eating more when you are already overstuffed is one example. Having a gruesome murder or crime occur every few pages may be another.
Seek the right balance in all that you do, so you can have the clear perspective to see the best opportunities for improvement!