“A superior thriller”(Oakland Press) from the #1 New York Times bestselling author—now in trade paperback for the first time. On his thirty-sixth birthday, Travis Cornell hikes into the foothills of the Santa Ana Mountains. But his path is soon blocked by a bedraggled Golden Retriever, who will let him go no further into the dark woods. That morning, Travis had been desperate to find some happiness in his lonely, seemingly cursed life. What he finds is a friend—a dog of alarming intelligence—and a threat that could only have come from the darkest corners of man’s imagination...