and that was it. we could find no other evidence. >> back at homicide, buffington showed the fibers to his superiors. >> lieutenant made a big joke out of it and told the rest of the squad that if i went over to the lieutenant's house and cleaned out the lint trap in his dryer, we could probably clear out all the cases in the city of atlanta. >> still, buffington sent the fibers to the state crime laboratory. a young forensic scientists, larry peterson, took a look. why was a fiber stuck in the crack of a shoe, why was that important? >> because it was somewhat loosely there. people normally don't have tufts of carpet fibers stuck loosely in their shoe. >> from those few thin threads, peterson would begin to build a case to try to catch a killer. how many fibers across the board did you look at every day in this case, when the case really