lester holt: jimmy said he pressed hall about jessie roach., recalling that september day in 1993. he was driving down a country road and he seen her walking her bicycle. lester holt: hall then told jimmy exactly how he abducted and killed jessie. you must have been revolted. oh god, lester, it was probably the hardest thing i've ever done in my life. to have to sit there and pretend to be his friend, to listen to this kind of stuff, and not just rip him apart. but i knew what the mission involved. i knew what was at stake for me. i knew what was at stake for the people's families that were still you trying to find their daughters. lester holt: a major transformation was taking place. jimmy was starting to care about more than just himself. and now, he was determined to squeeze the most crucial confession out of larry hall. and not just for himself, but for the family of tricia reitler. i started thinking, i don't know where this is still going to lead, how long this is going to take. but something's now happening. coming up, a disturbing disc