The Whisperers By John Connolly

In May 2009, just months after returning from Iraq, young soldier Damien Patchett commits suicide by shooting himself with a revolver during a walk. His father, Bennett Patchett, suspecting foul play, hires private investigator Charlie Parker to look into the matter. Strangely, on that same day, a police officer is found dead near the charred ruins of the infamous Blue Moon bar. In his investigation, Parker soon discovers that Patchett was part of a group of disillusioned ex-soldiers who frequently cross the border between Maine and Canada, a fertile ground for trafficking not only drugs, but also alcohol, people, and money. Meanwhile, a mysterious old man, sick but capable of ruthless violence, is approaching Maine seeking revenge. Charlie Parker will need the help of his friends Louis and Angel. Even so, he will have to confront a being he fears more than any other.