. >> for best-selling author douglas preston, it all began innocently enough six years ago when he decideda novel set in italy and with his family fulfill a longtime dream. >> we rented a villa in the country outside of florence with olive trees and cypresses around us and overlooking a vineyard. isn't it going to be wonderful? >> they made their home in the hills of tuscany, a gorgeous place steeped in history. just down the road was the villa of legendary explorer amerigo vespucci, after whom america is named. and right next door within sight of preston's house was another much grimmer landmark. >> the scene of one of the most horrific killings in italian history. >> a double murder, part of a string in which 14 young people were killed as they made love in cars on country lanes. an unholy amalgam of romance and violence. >> a lot of people would hear that there was a murder just up on that hill and be a little spooked by it. maybe move. find another house. >> well, i was a little spooked. obviously my landlord never said anything about it, but the thing is that it interested me. >> afte