20/20 Season 2010, Episode 19 : April 16, 2010

It seemed like a neighborhood right out of the 1950's, where adults kept an eye out for trouble and children walked home from school every day without fear. Until one day last October, when 7-year-old Somer Thompson seemed to vanish into thin air on a crowded sidewalk -- in broad daylight -- less than a mile from her home. Her body was discovered two days later in a landfill in Georgia, and the community was shocked to learn that there were 162 known sex offenders and predators living amongst them within a five mile radius of Somer's elementary school.