Apparently, slumber parties in the mid-South 1970s were plied with a strange ritual. At midnight attendees would gather before a mirror and chant "I don't believe in the Bell Witch" three times to see if the legendary spook would appear alongside their own reflections--a practice that echoes the "Bloody Mary" pattern following the execution of Mary Queen of Scots centuries ago. But that small circuit of preteen gatherings was neither the beginning...