admitted murdering laurie de pughs and provided clues to finding her body. >> there's multiple agencies look into him referencing unsolved disappearances. >> larry hall may have had more victims than ever imagined. >> we understand it's even more extensive than we ever thought. not 20 but maybe 30 to 40 in terms of the victims. >> that leaves 30 or 40 families still awaiting answers. which is why, says levin, it is critical that serial investigations do not stop. two decades after tricia reitler vanished, her father, gary, now believes larry hall knows where to find her. >> i think if larry knew what we go through on a daily basis, you