convicted drug dealer jimmy keene was on a mission. the prosecutor and put them away. if jimmy could get convicted killer larry hall to spill his secrets about another missing woman, jimmy would be a freeman. but winning larry's trust without raising suspicions was a tall order. now jimmy was about to get a chance to lock in larry's loyalty. here again is leicester holt with "the inside man." >> by the fall of 1998, after several months in missouri's toughest federal prison, jimmy keene could have won a popularity contest. he charmed everyone, just as beaumont knew he would. he even won over some convicts with his lending library of pornographic magazines. and he'd managed to placate "the chin" and the mob faction by day, while circling his prey, suspected serial killer larry hall, with one-on-one bull sessions at night. >> we just talked about a lot of normal things, hung out. made him feel like i was wanting to be his friend. >> but it wasn't fast enough for keene, who feared someone might recognize him and blow his cover. >> if you