The evening of January 5, 2005, was dry and cool in Graniteville, South Carolina. At 6:10, a 12-car Norfolk Southern freight train pulled up to the Avondale Mills textile plant, and Jim Thornton, a conductor with 18 years' experience, climbed down from the locomotive to open a switch and let the train roll onto a siding. It was getting close to the hour by which, according to law, the crew had to quit for the day and rest. After the workers had shut down the train, Thornton called a taxi to take him, the engineer, and the brakeman to a nearby motel. It never occurred to him that, for the first time in his life, he'd failed to check the position of a switch that he'd opened. All he thought, as the crew piled into the taxi was, "Lord, mission accomplished."