For anyone who has been there since the beginning of this series, and I strongly suggest you read the prior two installments before tackling this one, you recognize that author J. D. Barker has created something special. What is now known as the 4MK trilogy, named for the Four Monkey Killer from the title of the first book, THE FOURTH MONKEY, is the gold standard in modern serial killer fiction. I believe it stands right next to Thomas Harris' novels that featured such household-name killers as the Tooth Fairy, Buffalo Bill and the infamous Dr. Hannibal Lecter. This is high praise indeed, and I am confident that anyone new to these books will feel the same way once finished.

Anson Bishop has proven to be evil, cunning, brilliant and articulate in his extremely cold, calculated methodology to the victims he chooses to torture and murder. Why is he killing, and is there any significant reason for his toying with Detective Sam Porter? Thankfully, these questions and many more will be answered quite satisfactorily in this final entry of the trilogy. In fact, everything is so well-plotted and interconnected that it is difficult to present much detail without dipping into spoiler territory. Thus, I will highlight the action of this jam-packed novel that instantly grabs you by the throat and never lets up.

"THE SIXTH WICKED CHILD is a superior thriller. At over 500 pages, I can proudly say that there is not a wasted chapter, sentence or word here."

Of course, it starts with bodies. In this case, not only are the victims found with the signature tiny white boxes held closed by black ribbon that has been Bishop’s calling card, it also includes different messages spelled out by the bodies. The first ones have the words “Father, forgive me” written on a cardboard sign next to each victim.

It may seem to be biblical in nature, but it actually harkens back to a childhood memory of Bishop. Throughout THE SIXTH WICKED CHILD, we are privy to entire chapters depicting entries in a diary allegedly written by a young Bishop. Barker poses an intriguing question in the Author's Note: Can a serial killer be made? You may find yourself answering in the affirmative after reading these diary entries, which explore dark passages of underage children in a foster home being not only abused by their handlers but possibly part of a sex-trafficking ring supported by a bunch of dirty cops.

This should not provide any valid excuse for taking lives, but it does make members of law enforcement who are tracking down Bishop and reading these entries take serious pause. When Bishop is taken into custody, he pulls off perhaps the most brilliant twist of all. He provides enough evidence and room for reasonable doubt to completely turn the tables, naming Porter as the 4MK killer and himself as his unwitting pawn. The fact that Porter is on the run, supposedly following through on his efforts to nail Bishop, and that he suffers from memory lapse and PTSD from a shooting he was involved with in his first tour of duty with the Charleston P.D., leaves some definite room for doubt. Porter is now a vigilante, operating way outside the lines of the Chicago P.D. FBI agent Frank Poole has been brought in to capture Porter so that everything can be sorted out.

Meanwhile, Nash, Porter's partner with the Chicago P.D., along with several other colleagues, remain convinced that Porter is innocent. Bishop would have to be even more cunning and diabolical than anyone suspected to point any shade in Porter’s direction. But he does, and as readers, you will go through each and every scenario from the first novel to the last and reconsider all you thought you knew as you take another look through the eyes of Porter as the possible villain of the series. It is that seed of doubt planted by Bishop and expertly plotted by our humble author that will keep you turning pages in rapid fashion to get some actual, real answers.

THE SIXTH WICKED CHILD is a superior thriller. At over 500 pages, I can proudly say that there is not a wasted chapter, sentence or word here. Barker utilizes the formula that so many thrillers follow today: shorter chapters, each one told from the point of view of a different character. The difference is that each chapter feels like another puzzle piece that needs to be put together in the correct order and positioned by the reader in order to figure out where things are going. Rather than having the chapters end in breathless cliffhangers, the modus operandi of lesser thriller writers, Barker merely uses them to keep the narrative barreling forward to an unknown conclusion, where the only thing that is assured is that the finale will be well worth the effort.

I will miss this series, and I eagerly await to see what this supremely talented author has up his sleeve for us next.