Ten years later, hiker’s beheading continues to haunt investigator

It was bitter cold in early January 2008. But despite the frigid temperature, it seemed like the entire world had come out to search Blood Mountain in North Georgia. They were looking for Meredith Emerson, who had disappeared on a New Year's Day hike with her dog Ella.

It soon became clear that something terrible had happened to the 24-year-old University of Georgia graduate. That something was serial killer Gary Michael Hilton, who had encountered Emerson on the trail and overpowered her.

Ten years later, some of those closest to the case say they remain haunted by it.