Glen McSparren was taking a shortcut from his mother's house in Monroe County, Missouri, on a Friday night in April 2018, when he saw a car pulled over to the side.
It was a dark, backcountry gravel road surrounded by woods, with a creek running across the road. McSparren said he saw someone lying in the road as he got closer.
"My headlights came over on her body in front of the car," McSparren said. "When I [saw] her, I swear my heart stopped… I could tell she wasn't moving."
McSparren had discovered the body of 35-year-old Molly Watson. She had been shot once in the back of the head at close range. When he called 911, he said he was told to check for a pulse, but he already knew she was dead.
"I looked in her eyes, and I could tell that she was gone," he said.
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When police launched an investigation, they ruled out robbery gone wrong. Watson was found still wearing her engagement ring. A marriage license was found in the car with her and her fiancee's name: 51-year-old James Addie. Their wedding date was supposed to be two days after she was found.
Watson was someone who loved to sing, make costumes and posted video diaries on YouTube, her family said. She was excited to get married to Addie, and had bought two wedding dresses because she couldn't decide on one, said her cousin, Jodi Lindberg.
It was to be Watson's second marriage. Her first marriage ended in divorce. During the breakup, she became pregnant. After that, she was in a romantic relationship with a former childhood friend, Amber Brady, their relationship continued for about five years.
"She was actually my first girlfriend. I was hers. She was married at the time. I was too. So. But things weren't going well for either one of us," Brady said. "I think we could talk. We could communicate. We liked doing a lot of the same things … it just seemed to click."
But while they were living together, Watson got a new job at the Moberly Area Correctional Center in Moberly, Missouri, where she met Addie, who worked as a corrections officer at the prison. Brady said she caught the two of them at a motel together.
"I went up there and knocked on the door. She answered. James Addie was getting dressed and leaving … That wasn't good," Brady said.
Brady said there was another encounter at a gas station, where she saw Watson and Addie together
"I didn't have … any type of friendship or anything to do with Molly," when things ended, Brady said. "She had blocked me on everything, which-- that was fine. I mean, it wasn't a good breakup."
Molly’s brother Tim Watson said Molly was "absolutely, 100% in love" with Addie, who had been married four times.
After dating for seven years, Addie proposed to Watson and the two started planning a wedding for April 2018.
"There was a lot of burgundy and gold, kind of reminded me of a Renaissance kind of themed wedding," said Sam Cohen, their wedding planner. "From Molly's perspective, it was going to be a beautiful wedding and the best day ever."
"James was kind of the opposite of Molly," she continued. "He was very quiet, didn't show much enthusiasm. I just thought he was just a groom, along for the ride."
Chrystal Graves-Yazici and Tabetha Schilb, who were hired to do hair and make-up for the wedding, said it was supposed to be a Disney-themed wedding. The Walt Disney Company is the parent company of ABC News.
"She was so excited," Graves-Yazici said. "We had been working on a wedding that was 'Beauty and the Beast,' and so we were like, 'We're very familiar with doing this very Disney themed wedding.'"
But even as Watson was wedding dress shopping and invitations were being sent out, her family said they still felt uneasy about Addie.
"He could never look you in the eye. He could never talk to you directly. Everything was very evasive with him," Tim Watson said. "He put off bad vibes to everybody."
Some reached the point where they told her they weren't going to come to the wedding at all.
"My last [text] message to Molly… I said, 'But you know how I feel about weddings and funerals. I kind of have a thing anyway that I just kind of avoid weddings and funerals,'" Lindberg said. "Never would have thought that I would have been going to her funeral that next week instead of her wedding."
On April 25, 2018, two days before Watson was killed, she and Addie went to the county recorder's office to apply for a marriage license.
Mark Price, the Randolph County recorder of deeds, prepped the couple's license and said Addie seemed "perturbed" by some of his questions.
"[I asked] if he had been married before, and how it ended… he was just… like, 'Why do you need to know that?'" Price said.
Authorities say Addie claimed he and his wife Melanie Addie had divorced, and that she had been in a car accident and later died after being removed from life support. Cohen said Addie kept putting off wedding preparation meetings because he said he had to deal with funeral arrangements.
On April 27, 2018, the day Watson was murdered, Cohen said Addie dropped off centerpieces and decorations at the venue.
"He seemed just like he did in every other meeting that I met him … really quiet, didn't say much," Cohen said. "And I do recall, as I was walking him out the door, I asked if he's getting excited, and his one comment was that [Watson] was driving him crazy."
It was later that night that McSparren found Watson's body.
McSparren had actually been on that backcountry road once before that evening, taking his daughter to his mother's house. On that first trip, he said he had seen two cars. One was being driven by a short older man. McSparren said he asked the man if the other car was stuck.
"He said, 'I don't know where they're at. It's going to be awhile,'" McSparren said. "The more I thought about it, I was like, 'Something's not right … I'm going to go back through there.'"
That's when he discovered Watson and called the police.
Addie was convicted this year of first-degree murder and armed criminal action for Watson's death. He was sentenced in July to life in prison without parole plus 10 years.
He has long maintained his innocence and is currently working to appeal his conviction.
Addie did not take the stand at his trial, but read a statement in court during his sentencing, in which he read a love letter to the woman he had been convicted of killing. He also asked for a new trial, claiming his defense attorney was ineffective and didn't present all of the evidence in support of his case.
His now ex-wife, Melanie Addie, is very much alive and was never in a car accident. She says it was only after police showed up at her door the night of the murder that she discovered her husband of 23 years had been in a 7 year relationship with Molly Watson and was engaged to marry her
Melanie Addie testified against her ex-husband at trial.
She told “20/20” that she believes he's capable of murder.
"He was a pretty selfish person … He could be controlling and intimidating … it could be challenging," Melanie Addie said. "It just seemed like something he would do to fix a problem."