It's the story "They" don't want you to listen to. Though, to be fair, "They" are probably right about this one. To quote the Bible, "Learning the truth can be like loosening a necktie, only to realize it was the only thing keeping your head attached". No, don't put the book back on the shelf - it is now your duty to purchase it to prevent others from...
listening to it. Yes, it works with audiobooks, too, I don't have time to explain how. While investigating a fairly straightforward case of a shape-shifting interdimensional child predator, Dave, John, and Amy realized there might actually be something weird going on.
Together, they navigate a diabolically convoluted maze of illusions, lies, and their own incompetence in an attempt to uncover a terrible truth they - like you - would be better off not knowing. Your first impulse will be to think that a story this gruesome - and, to be frank, stupid - cannot possibly be true. That is precisely the reaction "They" are hoping for.