Something was off from the very beginning. A Dateline producer, Vince Sturla, had seen what was going on, enough to get a whiff of how odd it was. He called me from northern California just after Christmas, 2002. "You should come," he said.
It was a local story then. A young woman was missing, had disappeared Christmas Eve. She was nearly eight months pregnant. It seemed like most of the population of Modesto, California, was looking for Laci Peterson.
The police scoured the huge park near the Peterson's house; they investigated a burglary across the street, questioned scores of vagrants.
And then, a few days after Laci vanished, the police - along with Laci's anguished family - held a press conference. Vince and I attended and afterwards spoke to Laci's mother and her friends. They were eager to tell us about Laci's bright and happy personality. And... about Scott, her husband.
He was perfect for Laci, they told us. A caring husband, a man with real manners, who would never - ever - do anything to harm his pregnant wife, no matter what some people were whispering.
We also encountered Scott at that press conference. And we saw how he avoided the cameras, how he stayed out at the edge of things. He didn't want to be interviewed about his wife. Wasn't out beating the bushes looking for her. He didn't seem to be a part of what was happening all around him.
And then we saw a note Scott had posted on a bulletin board at search headquarters, which said, in effect, 'Laci is looking down on all of you." Looking down?
The police weren't saying much, but we knew they had their suspicions. Very strange. And so we aired a story on Dateline.
It wasn't much later when we dropped by Scott and Laci's house early one morning, hoping he might agree to talk to us. And just as we pulled up, there he was, taking out the trash.
He was very well turned out for a man engaged in domestic chores, casually but elegantly dressed, quiet, well-spoken and extremely polite. Yes, he saw our story, he told us. No, he didn't like it. No, he didn't wish to be interviewed.
By then we were fascinated and, pretty soon, we weren't alone. Media descended from around the country. Amber Frey was revealed. Scott's lies blared out from national headlines. Radio DJ's set up shop across from the Peterson house. A media circus came to town.
Why the fascination? The question has been asked many times, and I'm not sure there's a rational answer. What drew me then, and still does, is that last, infuriating dollop of uncertainty. For all the attention the investigation drew, for all the work that went into it - and into that very public trial - it's missing some piece of punctuation... which you could also call 'the smoking gun.'
In our new report, you see and hear central characters of the saga who are speaking in public for the first time. You'll see remarkable rare video. You'll get, perhaps, a better sense than ever about what happened to that lovely young woman named Laci Peterson and her unborn son Conner. And, yes, you'll hear about current attempts to exonerate Scott.
Here's what the detectives told me and producer Susan Leibowitz: It's true, there is no forensic evidence that absolutely positively convicts Scott Peterson… but there are many, many threads of circumstance, which prove his guilt as surely as could DNA.
The Laci Peterson Story: A Dateline Investigation airs Friday, April 21 at 9/8c on NBC.