The Fourth Monkey is the first book in the 4MK thriller series by author JD Barker. I've had this one on my TBR list for years and kept seeing it recommended in horror groups so I moved it up to the top. I enjoyed the gruesome crime and mystery elements. This is a great first book in a series and I am looking forward to seeing where it goes next. It wasn't nearly as graphic (in my opinion) as I had heard it made out. It reminded me a little of Chris Carter's Robert Hunter series, only way less gruesome. I liked the main character and the ending kept me guessing the whole way.