Dexter in the Dark at Amazon.Com
Our favorite serial killer - he only kills bad people - and star of his own television series, returns in his third and, for me, least satisfying novel. Lindsay attempts to explain Dexter's Dark Passenger (the force that guides him in his killing) in Stephen King terms. There is an original evil, referred to as IT, that has existed since the primeval ooze started life on earth. It floats around causing horrible things to happen and, incidentally, spawning Others, like the Dark Passenger that occupies Dexter. Having an outside force guiding Dexter rather than existing as an aspect of his personality makes Dexter less interesting as a serial killer. Your mileage might vary but personally I don't want Dexter to exist as a Stephen King/Dean Koontz clone.
In Dexter in the Dark, Dexter's Dark Passenger is scared out of him by the presence of IT. Without his dark Passenger Dexter is disconnected, unable to function and provide the insights on which his sister, police sergeant Deborah, has come to depend to solve cases. Burned corpses with heads replaced with the heads of ceramic bull are appearing. Dexter is being stalked by IT who recognizes that Dexter is occupied by an Other.
IT is also interested in Rita's children, Cody and Astor, who are also possessed of a Dark Passenger, or shadow, as Cody describes it. At the end of Dearly Devoted Dexter Rita and Dexter become engaged and, we learn, that her children have interests disturbingly similar to those of Dexter. This would have been a sufficiently satisfying plot - watching Dexter try to guide Cody and Astor the way Harry guided Dexter. Some of the more interesting parts of the story are when Dexter is "educating" the children.
The story runs out of energy toward the end and the forces of evil are thwarted in 8 pages.
If you are a Dexter fan as I am you will want to read this latest installment. Unfortunately I can't give it an enthusiastic endorsement.