The latest Kay Scarpetta book. Kay no longer works for the police/government, but has a forensic pathology practise.
This doesn't mean she's not uncovering what has happened to the victims of crime, but is now doing it privately.
A spate of murders don't seem to be linked, until they are looked at more closely. Kay finds a thread of a vague link and follows it through, it leads to the murderer.
In this book Marino is at his most obnoxious, and disappears, and still hasn't shown up at the end of the book. The reason for his bad behaviour being some pills he has been taking. So I presume that there will be at least one more book, as Cornwell can't leave her readers wondering what has happened to Marino.
http://www.patriciacornwell.com/books-novellas/book-of-the-dead/synopsis/