On Saturday, September 22, 1928, Barbara Griffiths, age four, strayed into the woods surrounding the upstate village of Massena, New York. Hundreds of people looked everywhere for the child but could not find her. At one point, someone suggested that Barbara had been kidnapped and killed by Jews, and as the search continued, policemen and townspeople alike gave credence to the quickly spreading rumors. The allegation of ritual murder, known to...