Transcript for 7 years after Lorenzen Wright’s murder, possible weapon found in lake: Part 6
Memphis tigers and the grizzlies has disappeared, and now his family is worried about his safety. . Germantown 911. Where is your emergency. Hello. This is almost like a tale out of a southern gothic novel. Greed, jealousy, false trails, envy, cold-blooded murder. It's compelling on so many It's a soap opera gone awry. Wright was found in a wooded area just outside Memphis. This is not only a news story, but it's a sports celebrity story. It's a murder story all wrapped into one. It's just one of those things that I could never put together. How does such an amazing guy end up dead and in a field? It was a case that, until we solved it, it was going to haunt us. It was literally going to haunt us. But his mother, god bless her heart, she continued to keep it in the forefront, to keep it going. I'm never ever, ever, ever going to give up. But Deborah wouldn't give up on it. She is absolutely the heroine. She is the hero of this story. She harassed, literally, the police department every day. She kept the heat on the she was in the news media for years, criticizing them for not doing enough to finding out who killed her son. She basically told me once I became the director, "You're going to solve my son's murder. And you are not going to get rid of me." You let everybody know that you would not rest until your son's killer was found. Yes. I wanted to solve it really, really bad. You know, not only for the city, for Lorenzen's mom and for his kids. I've never seen a mom to be that emotionally distraught over the murder of her child. And I've investigated a lot of murders. She was heartbroken. She was heartbroken, and that was very difficult for me to watch. So while the case has gone cold, Lorenzen's ex wife sherra has not withdrawn from the public, and many people are suspicious of that. The book she's written, supposedly fictitious, called "Mr. Tell me anything." It's making headlines and raising eyebrows. And it seemed to garner the attention of one man in particular, Kelvin Cowans. Cowans was a journalist who interviewed sherra about her book. He was one of the people I really wanted to talk to when I visited Memphis because of how close he says he got to her. What is "Mr. Tell me anything"? For me, it was the inside look at an NBA wife. What does the man do to the woman in this book? Oh, man. He breaks her. Her breaks her mind. He breaks her will. According to the book. Affairs. There is some domestic violence in there. I believe that the stories that were described in that book were based on what really happened, yes. It does make Lorenzen look like a really bad guy. In this book, there are specific descriptions of violence. What do you make of that? I just don't believe it. I think that is purely fiction. If he was all of that, why did she stay with him so long? She could have got a divorce at any time and got plenty of money. Girl, please. I don't believe nothing she say. If she tell me that her hair is black. I say, no, it's Orange. I just believed it. I was like, "She's baring all." Kelvin Cowans doesn't just believe her. He says he was romantically falling for her. It's something that as a journalist he admits was crossing the line. While they were dating, and even after they moved to Houston, she completely convinces him that she had nothing to do with Lorenzen's murder. I'm like, if she'd done something, they'd have her by now. I mean, I would have never moved away with her if I thought she was a killer. Sherra moved out of Memphis because she was tired of the suspicion and all the negative publicity she was receiving here. Did anybody know who she was in Houston? Did anybody treat her in a certain way because of that? No, no one treated her different. No one treated the kids different. It just wasn't -- it wasn't a subject. We were embraced in Houston. She moves to Houston, appears to live a quiet life. But one problem -- Kelvin said he never could quite get used to sherra's love for money. That was like, oh, my god. Not about money again. Cowans says they started arguing because he says long after the fight over the insurance money, sherra still wanted more from the estate. And he claims it blew apart their relationship. Why was it the last straw? Greed. I cannot believe that your apex of life is still, "How much more money can I get?" And you couldn't live with that. I couldn't. The relationship ends. Sherra moves to California with the kids to be near her brother, and Kelvin moves back to Memphis. Neither of them are aware that the Memphis police are about to take a new look at Lorenzen's murder. They call it "Operation rebound." They want to rebound, to use a basketball term, go through the evidence one more time, find that one key break. I received a phone call from the Memphis police department, and he said, "We want to run through everybody's story." By now Tony Armstrong has left the department, but he's still following the case closely. I immediately thought, "Okay, somebody has gotten themselves in a tight spot, and they're starting to talk." The police suddenly announce, "We found the murder weapon in a lake in Mississippi." News about finding at least one of the guns was all over local news. Seven years later, the gun the killer may have used was found in a lake in walnut, Mississippi, in tippih county. How did you hear about them finding the gun in the lake? They called me. The news got around town -- they found the gun. They found the gun. And I'm like, what? You found -- like, after all this time? Liker how? And now the next thing I'm thinking, okay, now who was it? Who killed Lorenzen? And that's when this man enters the story, a man who cops say is the whole reason they found that gun in the lake in the first place. Because he claims he knows who put it there. You mean what? Are you kidding me?
This transcript has been automatically generated and may not be 100% accurate.