according to jeter, crystal's boyfriend, paul hargrave, was the one the family pointed fingers at. >>hey didn't know anything about him. he was the boogieman. >> then the boyfriend was brought in for questioning. and he, too, cooperated. handed over those videos, his cell phone, and agreed to be strapped to the polygraph. and? >> failed miserably. >> he did, too? >> yes, sir. >> that's a dilemma. you have the husband and the boyfriend failing the polys. >> both on saturday. >> i'm like, what the hell is going on? i just -- i couldn't believe it. and i thought, well, maybe they're in it together. you know, that really threw us off. really threw us off. >> the skies may have cleared, but that didn't mean any new light was shed on the investigation. everything seemed just as dark and confusing as before. it looked as though the only way to solve this mystery was to find crystal or her body. >>> coming up, caught on camera -- a rider in the storm. >> when we saw him riding a bike, we said, that's what he did. >> when "dateline" continues. nup with the cooking. but she wanted someone who l