Adam follows a profiler named Daniel who is obsessed with finding a serial killer known as Eve. Eve kills young girls each month during the New Moon cycle - when it's the darkest. Daniel's obsession has led to his divorce which is a tad cliche but we can forgive Dekker that bit.
Throughout the novel, there are nine excerpts from a crime magazine that records the story of two children who were kidnapped and how they were raised. Using the articles helps as a form of back-story and building a suspense for the overall story.
I enjoyed reading Adam. However, I won't jump into the camp of people who said it was so scary they had to sleep with the lights on. (As one of the editors for the book said) I didn't find it scary. Perhaps I'm used to the Dekker thrills. But having said that, it didn't cause me to enjoy the story any less.
What did lessen the book's quality was the continued use of words. Words that had to have been substituted for swear words to lessen the objection of Christian readers. Dekker had his characters say "whore" and "sow" and "pig" over and over when I thought it just made the characters seem, I don't know, not whole. My problem with this complaint is that I don't have a comparative solution. I just didn't think using those words as often as he did, worked.