The Mysterious Murder of Jeanette De Palma

In Springfield, New Jersey, on September 19, 1972, a dog returned from a wooded area carrying an object in its mouth. The dog’s owner approached to investigate what seemed to be a "large bone" and let out a scream when they realized it was a human arm!
Search teams located the rest of the body, which was found fully clothed in a small clearing atop a steep hill, lying face down, with an odd, almost ceremonial rock formation found around it.
Dental records identified the deceased as 16-year-old Jeannette DePalma. She had been reported missing by her mother six weeks earlier.
But with only a name to go on, the police now had the daunting task of finding out what truly happened to Jeanette, and more importantly… why?