investigator gary miller got the call. >> we all knew that we had something really bad here.had an abduction. >> jessica's badly decomposed body was found in an indiana corn field weeks later, but then, like tricia's, jessica's case went cold. >> there's a lot of times you wonder whether you'll ever solve it, but you know you're going to keep going, check everything out, recheck everything. >> for over a year, miller scoured local police reports, and then, a break. a vehicle reported in a county nearby, the owner, larry hall. >> he had been involved in stopping some girls. those girls were scared. they ran from him. >> in the last six months, hall's van was spotted by more than 11 girls in five different towns close by. including those where jessica lived and where her body was found. now miller contacted the police in hall's hometown to arrange for an interview. >> he initially said no, he hadn't been over here. >> miller had to coax hall to admit being near jessica's house. >> i said, well, would you remember if you stopped and offered girls a ride or asked them to get in y