Not pleasant. Reporter young women murdered were missing. Families in anguish. I would text her and she would text back. Nothing. When they killed her, they killed me. Reporter a Serial Killer at work and maybe he had a friend. That is crazy. Serial killers are loaners. Everywhere. Reporter to suspected killers on the hunt. Hunting them. A detective devoted to justice and more. It is almost like he adopted these young women. A lot of visits to my Local Church saying, dont screw this up. Welcome to dateline. They were young women with their whole lives ahead them. Then One By one, they started to vanish. It take a determined detective willing to go into dark places to uncover the diabolical plot behind the disappearances. Here is t more send with good evil. Reporter how do you measure a mothers love . Or gauge the ferocity of her impulse to protect. Love her as much as i could, was the thing. Reporter how to measure love as visceral as the Beating Heart in her own body. She was my first
in both locations. she called detective trapp. there s only one person. she s like, i know him. i said, who? and she s all, his name s franc cano, he s a registered sex offender. reporter: in 2007 franc cano pleaded guilty to committing a lewd act on a minor. he was now on parole wearing a gps monitor. but now next question, did franc cano s monitor put him near the places those other three women, according to phone records, made their last calls, kianna, josephine, and martha? one by one, the detective entered the coordinates. and every intersection for that date and time that they gave me, franc cano came up. reporter: wow. for every single intersection. it was it was i was shocked. reporter: but something about that man, franc cano. he had a buddy.