. >> it is a story keith morrison followed for nearly ten years. >> how? when? >> i get a call from her boss, said she hadn't showed up for work. >> they found her in the car. >> i saw in the back of her neck some ligature marks. >> just didn't deserve that. >> a small island, a small pool of suspects. ryan, her lover with the past -- >> i had no idea he was a drug dealer. >> and darren, the soon-to-be ex-husband. >> that morning he called in sick. >> was darren polygraphed? >> he didn't pass. >> and the lover? >> he didn't do that good either. >> without much else to go on, this case was growing colder by the day. >> nothing. just nothing happens. >> but a father doesn't forget. >> i have to have justice for my daughter. >> after all these years, are there still secrets to uncover? >> must have been quite a journey for you. >> it isn't over yet. >> this father finally got his answer, but is it the one he wanted? >> never in my wildest dreams would i have imagined what we're going through now. ♪ >>> hello and welcome to "dateline." sandra galas was born and rais

here's keith morrison with "everything she knew." >>> it was a monday morning in january 2007, 9:08 a.ma young woman in san antonio texted her boyfriend. "i love you." that's all it said, "i love you," nothing more. downtown the alamo had just opened its doors. a few tourists began boarding little boats to gaze at remnants of texas history along urban stretches of the san antonio river, and several miles away in the farther reaches of the modern city a manager of a video game store began his daily ritual. his name was mariano rivera. >> the store opens at 10:00 but managers get there at 9:00, grab the till, the money and take it to the bank. >> same process at a sister store, same company, not far away. that one managed by a woman who sent the text to her boyfriend, except this was strange. as the morning slipped by, her store remained closed. mariano got a call from the district manager. >> can you go over there and maybe you can see something, see what is going on. >> he did. he saw a white car in the parking lot. looked like the young woman's car. he peered into the store window. nob

here's keith morrison with "the motive." ♪ >> reporter: her heart was on fire. lost to her. canned music, the hum of other voices in the bar. there was only him. they were in the deep end now. and as lovers in the flush of new commitment sometimes do, they confessed their sins of the abandoned past. the worst things they'd ever done. words, just words, best forgotten until they could no longer be ignored. ♪ lexington, kentucky. one year before that night in the bar. a house where students lived. and the music and laughter and chatter of a birthday party swelled and ebbed and drifted in and out of the evening air. >> it wasn't a huge party. it was just a low-key party with some good friends. >> reporter: they were about to be seniors, the young men who'd rented the place, who'd hosted the party. >> we had a group of guys, four guys that got along extremely well. >> reporter: they were big men on campus. they played football. the university of kentucky's beloved wildcats. antonio o'ferral was a quarterback. >> in lexington, kentucky if you play for the cats, you're pretty much

here's keith morrison with "the threat." >> reporter: on the southern bank of the columbia river, tucked away in a corner of this little cemetery is the final resting place of a woman called joan. barbara joan lockwood. she wasn't a famous woman, joan, wasn't rich or celebrated. she lived a quiet life in a quiet place and was buried here more than three decades ago, but if ghosts could rise from their graves, if joan could speak to us now, what questions could she answer, what advice for this man, this tough, aggressive prosecutor who now fears for his life? >> this man is a threat to me. he's a threat, more importantly, to my family. >> reporter: in the anils -- sometimes they refuse to die. sometimes they lay and fester. >> it begins with joan. she lived when she lived 1,000 miles south of that little cemetery, a few miles from the beach in l.a. in a suburb called torrance. on a quiet street named sharon lane. there was joan, her husband bill bradford and their four children. this is joan's only daughter, shawn. >> people would describe her as the most caring, sweetest person they ever

here's keith morrison with "deadly trust." >> reporter: there's a place. call it a pot of gold at the end of ambition, of the american dream. a place the few and lucky build their mansions by the sea. newport beach, orange county, california, where the most unexpected event would be murder. >>> things like this rarely happen in newport beach, let alone in an area as secure as this area. >> reporter: let alone involving people like this, attractive, charismatic, living large. like nanette johnston packard mcneal. >> she had a beautiful home, she drove an expensive car, and she was sort of living that dream california lifestyle. you talk about "housewives of orange county," she could have been on the show. >> reporter: yes. in fact, she told friends she turned down an offer to be on the show, about excess in orange county. she ended up on a show called "american thunder" about motorcycles, showing off her own excess, including a bike she bought for 50 grand. >> what's your favorite part of the bike? >> i love the way it looks. >> reporter: and then there was

here's keith morrison with the "summer of manson." >> all that remains are ruins. the ramshackle barker ranch is long gone. only the fitful baking death valley wind left now to stir the faded bits, the rusted junk. the artifacts from another time when this was ground zero for one of the most infamous crimes in history. the hideout of a living personification of evil. >> you got it stuck in your brain that i murdered somebody. >> charles manson. one hot, dry weekend in los angeles, august 1969, a pregnant movie star slaughtered, along with four others in her home, across town a couple butchered in theirs. >> these were brutal crime scenes. things that the police had never seen before. >> reporter: murder so bloody, so ugly, they rewrote history. became a kind of bookmark as an era of optimism ended and a darker time began. >> the '60 came to a close, 1969, and that was the curtain. that was the final curtain. >> who could make sense of it? >> are you sane? >> sane? >> yes. >> that's relative. >> who even now. >> how do our kids end up doing this kind of incredibly v

here's keith morrison with "good and evil." >> reporter: how do you measure a mother's love or gaugehe for ross -- ferocity of her impulse to protect? >> i loved her as much as i could. >> reporter: how to measure love as visceral as the beating heart in her own body? >> she was my first born. she was my best friend. >> reporter: how to understand the four mothers you will meet tonight and their connection, one that not one of them would ever have thought possible, not in a million years. anymore they would have expected to meet her, their guardian angel. >> if i don't bring her home, who will? >> reporter: it's a rare mystery that's truly a confrontation of good and evil. >> you have to go to the dark places in order to find answers. >> reporter: a rare mystery that needed an urgent answer before the evil struck again. it was march 14th, 2014, early morning. an army of garbage trucks made their growling clanking way in a anaheim, california. their destination a landfill that is also a literal mown dane of garbage, 500 feet high. then mid-morning, an attendant separating debris on a

. >> it is a story keith morrison followed for nearly ten years.