Produced by Lourdes Aguiar

[This story first aired on Jan. 19. It was updated on June 29.]

Betty Jones and her friend Kathryn Crigler were brutally attacked on Labor Day in 1990 after answering a knock on the door at Crigler's Starkville, Miss., home. Jones, who opened the door, was stabbed immediately and died. Crigler, who was in a wheelchair, was in the rear of the home. The killer walked back to Crigler's room, raped her, strangled her and left her for dead. Crigler was able to crawl to a phone and call for help. She died two months later.

Starkville detective Bill Lott says the crime scene "was as bad as anything Jack the Ripper ever did."

"It's frustrating," Lott told "48 Hours" correspondent Richard Schlesinger this past summer of not yet having solved the crime. "Yeah, it's frustrating, no doubt about it."

The case, which was unsolved for three decades, prompted Betty Jones' step-grandson, Jason B. Jones, to spotlight the case in a podcast. Jones, who was 10 at the time of the murders, launched his podcast in September 2017 as a way to work through his own questions about the incident and, perhaps, have someone uncover new information.

But what began for "48 Hours" as a story about a cold case turned into something much different, thanks to Lott's determination and cutting-edge DNA technology that didn't exist when the women were killed.

"Even though I'm a dinosaur, I'm constantly getting on the Internet and looking at science," said Lott.

That trail led him to Parabon NanoLabs in Reston, Virginia, which developed technology that can predict what someone looks like through DNA.

"It's like, 'now I know what you look like,'" Lott said. "'Now I'm going to get you.'"

"I've just felt an electricity about that this is going to be solved sooner than later," says Juky Crigler Holt, the granddaughter of Kathryn Crigler.

Will technology help solve the case and get long-sought-after answers for the Jones and Crigler families?

A KNOCK AT THE DOOR

Jason Jones has a job he loves. He designs album covers and produces music videos in Nashville, Tennessee. But for more than a year, he had a second passion. He had a podcast — a dark podcast — and it was personal.

"KNOCK KNOCK" PODCAST: I will never forget that night … I remember waking up in the middle of the night sweating.

Jason launched his podcast in September 2017. It had an odd title, "Knock Knock," and is about a particularly vicious crime that had been unsolved for nearly 30 years.

"KNOCK KNOCK" PODCAST: I can't imagine the terror that Betty and Kathryn felt when they realized behind that knock, knock ... stood a monster.

For Jason, this was more than just a murder tale — it's the story of his family. Betty Jones was his step-grandmother.

Betty Jones with her step-grandson, Jason B. Jones. Jason B. Jones

Jason Jones: I think that there was this [signals with his hand like a flatline] this hum of fear throughout our family after Betty died.

It was Labor Day 1990. Jason was 10 years old and living outside of Houston. That's when his family got that phone call telling them Betty had been murdered in Starkville, Mississippi.

Richard Schlesinger: Were you scared?

Jason Jones: Oh, yeah ... I knew enough to know that there was someone out there that killed my grandmother and they may wanna kill me, too.

Jason's parents Bill and Colleen Jones struggled to explain it all to him and his younger brother Simon.

Richard Schlesinger: Do you remember the words you used?

Colleen Jones: "We don't know why, but God called Betty home and you'll see her again someday."

Betty came into their family late in life. She was a widow when she married Jason's grandfather. He already had two grown children including Bill, Jason's father.

Bill Jones: She was wonderful …she took us in as her own children you know and was just warm and loving and just an angel to me.

Sadly, Betty's marriage to Jason's grandfather did not last long.

Jason Jones: My grandfather passed away from a heart attack just a few years into their marriage.

Although Jason only knew his step-grandmother for a few years when he was young, she left her mark.

Jason Jones: She was the lady that came over and took us to nice restaurants and smelled really good. That's how I remembered her as a 10-year-old. She was the grandmother that was really into baseball which ... for a little boy, havin' a grandmother that's into baseball is pretty cool.

Betty Jones was the baseball team mom for the Mississippi State University Bulldogs Starkville Police Department

Betty Jones was more than just a baseball fan. She was a team mom for the Mississippi State University Bulldogs in Starkville. Her job was to keep the players from getting homesick and wanting to leave.

Betty's sister, Anne McWhorter, says Betty often brought the players chewing gum to keep them from other vices.

Anne McWhorter [imitating Betty]: "Now, honey [laughs]. I want you to be sure and chew that gum. Now, don't you get into that tobacco!"

Richard Schlesinger: She had a real connection with this baseball team.

Anne McWhorter: She did, but she had a connection with any age person.

Kathryn Crigler was one of the people to whom Betty felt connected. Betty was 65; Kathryn was 81, a retired school teacher. She was taking some new medication and Betty volunteered to keep her company in case she fell ill.

Richard Schlesinger: What was the basis of their friendship?

Juky Crigler Holt: Church.

Julia Crigler Holt, known as Juky, says her grandmother and Betty were active members of the First Presbyterian Church, which was right next door. Betty was a church elder. Kathryn sang in the choir and she played the piano at home.

Juky Crigler Holt: I think that was her dream for me to be a pianist. That didn't happen, but I took lessons for her.

To this day, Juky has warm memories of her grandmother's house. Kathryn had raised two children there and it was a gathering spot for extended family.

Juky Crigler Holt: Her house was a quaint little house. I never, in a million years, would ever feel scared in that location.

That night in 1990 started out peacefully enough. The two friends were just settling in after suppertime. That changed around 9 p.m.

Juky Crigler Holt: They had taken baths, they had their gowns on, they were getting ready to watch a ballgame when somebody knocked on the door.

David Lindley | Retired Starkville Police Chief: The monster came to the door.



David Lindley is now retired. but he was the lead investigator at the time. He says when Betty opened the back door, an intruder forced his way in.

David Lindley: As best we can tell entered into a physical confrontation with her. And she tried to defend herself.

Kathryn Crigler was left bleeding. She had fractured ribs and a broken hip. But she somehow managed not just to survive — but to call for help. Julia Holt

Kathryn Crigler was all but helpless. She was an amputee and she was in her wheelchair in the bathroom when she heard Betty calling for help.

David Lindley: She tried to see what was goin' on and the attacker appeared. He ended up makin' her go into her bedroom ... and told her that he did not want to hurt her like he had hurt her friend ... he in fact did rape Miss Crigler ... And he left the residence sometime shortly thereafter, we surmised.

Kathryn was left bleeding. She had fractured ribs and a broken hip. But she somehow managed not just to survive — but to call for help.

David Lindley: Miss Crigler was able to — rally her strength ... she couldn't get to her wheelchair. So, she took a pillow and — used it to — kind of glide or slide into the kitchen area, where there was another phone and she was able to reach up.

911 OPERATOR: Are you Miss Crigler? KATHRYN CRIGLER TO 911: Yes. Tonight there was one single boy — a young man — and he went in the front room where my friend was and he came back with his hands all bloody. And then he raped me. I know, it's just terrible.

Kathryn was rescued by EMS, but, in the living room with the baseball game still playing on the TV, Betty was dead on the floor. Her throat was slashed. She died trying to save Kathryn.

Anne McWhorter: She was a fighter. And I know that when this guy started attackin' her, Betty fought back like a wild cat.

Betty's death left a hole in her family's life and everyone in the small university town was on edge. As it turns out, police wouldn't have to look far for a good suspect … there was one right next door to Kathryn's house.

THE HUNT FOR A SUSPECT

Even now, it's hard for Juky Crigler Holt to think about the details of what happened to her grandmother, Kathryn.

But Juky is still amazed by the courage and the strength her grandmother summoned after she was attacked, to get help for herself and her friend, Betty.

"I think to look at these pictures — it makes me sad. How horrible it is to know that at the very last part of her life something so horrible would happen," said Juky Crigler Holt, pictured with her grandmother, Kathryn. CBS News/Julia Holt

Juky Crigler Holt: It makes me proud of her. Because she could've totally just given up right then. Most people would ... That's pretty amazing.

Sadly, Kathryn was unaware at first that Betty was killed.

Juky Crigler Holt: Clearly what I can remember her saying all the time was, you know, if anything ever happened ... to Betty, I don't want to live.

Betty's stepson, Bill Jones, visited Kathryn in the hospital after she learned her friend was dead. It was an emotional visit.

Bill Jones: She was upset that she survived and Betty had gone.

Richard Schlesinger: Do you remember what she said?

Bill Jones [emotional]: She said, "I'm so sorry. Please forgive me, please forgive me." And I said, "I forgive you."

Richard Schlesinger: Did you feel that she was responsible?

Bill Jones [Shaking his head] No ... it tore me up. But that's all I could say or do, and that's what she wanted, so that seemed to help.

In November 1990, two months after the attack, Kathryn Crigler died of complications from her injuries.

Richard Schlesinger: There's no doubt that whoever killed Betty that night, killed your grandmother ... It just took longer.

Juky Crigler Holt: Yeah, absolutely.

But Kathryn had lived long enough to give the Starkville police a description of the assailant.

David Lindley: She said he was a young man … Short hair that was almost cut like a crew cut — spiked, I guess you would say these days. He had blue eyes and light blonde hair or brown hair.

Police released a rudimentary sketch.

David Lindley: She described his complexion as swarthy ... And we imagined that to be something either as — a skin tone or a suntan.

Investigator David Lindley says the killer left a few clues behind.

David Lindley: We collected fingerprint evidence, we collected hair evidence, blood —

Richard Schlesinger: You found some cigarettes there.

David Lindley: We did … And neither of the women smoked. And — so we of course assumed that the perpetrator left the cigarettes at the scene.

But the police could not figure out a motive. The killer took $28 from Kathryn, but nothing else. And Lindley didn't think a petty thief would commit a crime this violent.

David Lindley: But in this particular case there was just no rhyme or reason for it ... This is a crime of violence, purely for the sake of violence.

The hunt for a suspect was intense and police had a lot to work with. Lindley provided an update soon after the killing back in 1990:

DAVID LINDLEY TO REPORTERS: Residents of Starkville are extremely helpful in providing leads and right now we have several leads that we are pursuing.

Many of those leads, like a report of a drifter spotted in the area, went nowhere. But a good suspect soon emerged. A young neighbor of Kathryn Crigler's was having a party at his house the night of the attack. He had blonde hair and blue eyes — just like the killer Kathryn described.

A rudimentary sketch of the suspect was later updated to show hair and eye color Sgt. Bill Lott/Starkville Police Dept.

The more police investigated, the more their suspicion grew.

David Lindley: He did leave the party for a period of time. ...But nobody at the party could recall for exactly how long he was — gone from the party.

What's more, the young man was known to carry a knife and he smoked the brand of cigarettes found at the scene.

Richard Schlesinger: Well, that must have caught your attention.

David Lindley: Certainly.

The suspect also reportedly made a cryptic and possibly incriminating statement to a witness when asked about the crime.

David Lindley: He stated that he did not do it, but his other self may have done it.

Police had a lot of suspicion but did not think they had hard evidence to arrest him.

David Lindley: There was never enough probable cause to make an arrest … I think a lot of people in the community naturally believed that this individual committed this crime … They wanted it resolved quickly, but unfortunately it didn't occur that way.

Police were back at square one and, after three years of dead ends, investigators turned to "America's Most Wanted," which agreed to feature the case. Everyone had high hopes.

Anne McWhorter: Well, I was hoping that somewhere up in Chicago or California someone would … brag in a bar … you know, "I was in Mississippi at that time. And [whispers] — hey, I did it. I did it."

David Lindley helped man the phones at the show's headquarters in Washington, D.C.

David Lindley: We received many, many tips from all over the United States.

It looked promising, but only for a while.

Richard Schlesinger: Anything pan out?

David Lindley: They did not … It was unsuccessful. A good attempt, but again, unsuccessful.

Richard Schlesinger: The level of hope that you must have felt.

David Lindley: This case has been a heartbreaker over the years ... So, disappointing is a good word.

In 2004, Lindley — who by then had been promoted to chief of police — handed the case over to an enthusiastic detective named Bill Lott. And Lott was intrigued by this case.

Sgt. Bill Lott: When I first got assigned this case, I didn't do anything for the first year but read it six times ... I bet Chief Lindley thought, "when is this kid gonna start workin' this case?"

But as Lott dug in he became confident that the case could be solved.

Sgt. Bill Lott: And I knew at that point I had a critical piece of evidence.

A CHANCE MEETING

Sergeant Bill Lott's roots run deep in Starkville, Mississippi. And he has struggled for years to solve the mystery that has hung over his town since Labor Day of 1990.

Sgt. Bill Lott: And to think that somebody would do something as heinous as this to elderly people just — it made me angry.

Lott feels a personal connection to Betty Jones and Kathryn Crigler.

Sgt. Bill Lott: Because — my parents had divorced at an early age and aunts and uncles helped raise me. And they were older. I had an older aunt that, you know, played a role in my life ... it just didn't sit well with me.

"48 Hours" correspondent Richard Schlesinger and Sgt. Bill Lott CBS News

When Lott took over the investigation in 2004, he inherited boxes of evidence, hundreds of pages of police reports, and a decade-and-a-half of frustration.

Sgt. Bill Lott: Let me tell ya somethin' — there was a lot of great, great detective work done ... The only advantage I had over those guys was DNA.

That's because when the crime was committed in 1990, not much was known about forensic DNA. But with new knowledge and new technology, Lott knew he had potentially critical evidence, because doctors had extracted DNA from Kathryn Crigler using a sexual assault kit.

Richard Schlesinger: They might not have known it at the time but that was a key moment in this case.

Sgt. Bill Lott: There's no question about it … that was the key to the gate.

Police kept the evidence and in 2005 Lott sent it to a lab.

Richard Schlesinger: What did that lab do for you with this evidence?

Sgt. Bill Lott: They got a semen-based DNA profile.

With the DNA profile of the killer in hand, Lott's first order of business involved an old suspect: that blond-haired, blue-eyed man who was partying next door to Kathryn's house.

Richard Schlesinger [with Lott looking at a container of evidence]: What is this?

Sgt. Bill Lott: This is — contains the original kit of the number-one suspect that supposedly did this crime.

Lott had the killer's DNA profile compared to the DNA of the young man who many in Starkville still believe had been responsible.

Richard Schlesinger: What did it show?

Sgt. Bill Lott: Not a match.

Richard Schlesinger: Not a match?

Sgt. Bill Lott: Right.

The one-time prime suspect was almost certainly not the man who killed Betty Jones and Kathryn Crigler. In 1990 there was a lot of pressure to arrest that man. And Lott believes if he had been arrested he would have been convicted and executed.

Richard Schlesinger: Has this case ... changed the way you feel about the death penalty?

Sgt. Bill Lott: I'll say it this way. I used to 100 percent pro-death penalty.

Richard Schlesinger: Now?

Sgt. Bill Lott: [Sighs] Now I think it would have to be on a case-by-case basis.

Richard Schlesinger: Sounds like a shift to me.

Sgt. Bill Lott: Yes, because he could've been put to death for a crime he didn't commit.

Lott went on to test the DNA of 60 other potential suspects; none was a match. There was also no match in CODIS, the national DNA database of violent criminals.

Anne McWhorter | Betty Jones' sister: I had resolved that it would probably never be solved ... that I would go to my grave without knowing — who did this.

Hours away in Tennessee, Jason Jones and his family — who had grown distant from Betty's over time — knew little about the investigation.

Jason Jones: No one was calling us. We were the extended family.

And Jason says over the years his family hardly ever spoke about Betty' s death.

Jason Jones: It becomes this taboo subject where people don't really disclose information because it's hard to talk about.

But now, as an adult, Jason was more curious than ever.

Jason Jones: I wanted to know what had happened, and so I Googled it, and nothing came up ... it was shocking to me that I couldn't find information about this case or my grandmother's murder or her life or anything.

He had questions about Betty, but he had even more about Kathryn Crigler.

Jason Jones: I don't think I knew the name Crigler, to be honest.

Richard Schlesinger: You didn't know the name of the other person.

Jason Jones: I don't think so.

But in August 2005, when Jason was getting married, there was a huge, almost unbelievable development. His fiance's mother held a bridal shower and invited some of her friends. Stories frequently come out of bridal showers, but not like this story:

Colleen Jones: I was busy playing mother of the groom. And — so I was introduced to a lot of people that day.

Jason's mother Colleen was chatting with a young art teacher when they discovered that even though they were both in Nashville, they had a Mississippi connection.

Colleen Jones: And I told her that I had married a guy that had gone to high school and college in Starkville. And she said, "Starkville? My grandparents lived there. What's your husband's last name? What were your in-laws' last name?" And as soon as I said, "Betty Jones" … it was just like she had seen a ghost, and I was it.

Standing before Colleen Jones was Kathryn Crigler's granddaughter, Juky.

Richard Schlesinger: Well how did you feel?

Juky Crigler Holt: Just wow! You know? What are the chances?

Richard Schlesinger: Well, you tell me [laughs]. What are the chances?

Juky Crigler Holt: Yeah, one in a gabillion. You know? It's amazing.

Both women were quick to see a larger meaning to the chance meeting.

Colleen Jones: This cannot be coincidental, happenstance ... It's like the angels went [she sings] "ahhhh."

But it wasn't until 2017 that Jason, who was inspired by true-crime podcasts, decided he should spotlight the cold case.

"KNOCK KNOCK" PODCAST: Even as a child I learned what the monsters fear. Whether imaginary or real — monsters today still fear the light.

Jason Jones: The podcast was not only a way for me to learn more about the life of a grandmother that was taken from me too early ... but also a way to try to seek justice or to make sense of what happened.

Working on the podcast would force Jason to return to the place he last saw when he was 10 years old — Starkville, Mississippi.

Jason Jones [in Starkville]: It's always been a story. And on this trip, it just — progressively became more real.

But it's always been real to Sergeant Lott who has never given up and believes one of Starkville's oldest cases with be solved with the newest technology.

Sgt. Bill Lott: And I wanna get this guy. And this is a good tool. This is as good a tool as we've had in a while.

CUTTING-EDGE TECHNOLOGY

In early 2017, Jason Jones traveled to Starkville, Mississippi — a place he had long associated only with death and sadness.

Jason Jones: This just feels like Pleasantville, USA.

But visiting the home where his step-grandmother spent the last moments of her life brought back those familiar dark feelings.

Jason Jones [inside the house]: I just feel overwhelmed here. It's not even sadness it's — there's just a magnitude. I don't know. It's hard to describe.

Jason Jones: I hadn't visually put together that this was a real place with real walls and real windows.

Jason Jones [inside the house]: Now that I am here I could, I could really understand what it would be like this ... that's ... that sense of being trapped and — and that overwhelming panic.

Being in this place and knowing what happened here made it even more important to Jason to find out who was responsible, and to share the search with his listeners.

"KNOCK KNOCK" PODCAST: How is it that we could have untampered DNA evidence, yet no matches had been made? If we couldn't find a match, honestly, could this case ever be solved? CBS News

But Sergeant Bill Lott was still working this case, often on his own time.

Sgt. Bill Lott: I told my wife, I said, "If I retire and I still haven't solved this case, you're gonna be rollin' me up to the police station in a wheelchair where I'm working on it ... I'm not quittin."

And DNA technology is improving quickly. In June 2018, Lott had the suspect's DNA profile sent to Parabon NanoLabs in Reston, Virginia. Parabon works with cutting-edge technology performing what is called DNA phenotyping.

Dr. Ellen Greytak: DNA phenotyping means predicting a person's appearance from DNA.

Dr. Ellen Greytak is Parabon's lead scientist for DNA phenotyping.

Richard Schlesinger: How new is this technology?

Dr. Ellen Greytak: It's very new. It's been available to law enforcement for less than four years. And at the beginning, there was a lot of skepticism ... DNA was seen as having this one purpose for matching. And we were saying, "No, there's all this other information you can get from DNA.

That's because DNA is like a blueprint for a person's ancestry and physical characteristics. There are DNA codes that tell the color of your eyes, your hair, and your skin. The codes also tell your face shape, and even if you have freckles — and how many.

Dr. Ellen Greytak: And we've trained up our computers to recognize those genetic signatures ... And then if we run a crime scene sample from an unknown person through that model and the computer recognizes one of those signatures, it can say, "There's a high probability that this came from someone with blue eyes." ... And then as you add each trait, you end up with a smaller and smaller group of people.

Richard Schlesinger: If I'm a cop looking for a needle in a haystack, it seems to me you've just taken away a lot of hay.

Dr. Ellen Greytak: Absolutely. It is extraordinarily helpful with eliminating a lot of suspects … and focusing an investigation.

Parabon showed "48 Hours" how they came up with the composite in the Starkville case.

Dr. Ellen Greytak: We've got the predicted face shape and we've got the predicted skin color on there. But we don't have the predicted eye color or predicted hair color.

But this process is part science, part art.

Richard Schlesinger: This is sort of a blank canvas, to use an artistic analogy.

Thom Shaw is a forensic artist who interprets the computer's conclusions and makes the image more lifelike. The computer had concluded that this killer would most likely have some freckles, brown hair, and light blue eyes.

Thom Shaw: And so then I can go … to that collection of light blue eyes and pick out, "OK, this is — this is the one we like."

Dr. Ellen Greytak: And we're not producing a photograph. So we don't know the person's age, their weight, anything that they've done with their hair or tattoos, scars, things like that. But we can give a description, which is something that the — that these detectives didn't have before.

In late August 2018, Parabon sent Sergeant Lott two composites: the first one, pictured at left, showed an idea of what the suspect looked like in 1990; a second composite was age progressed to show what he might look like now. Parabon NanoLabs, Inc

In late August 2018, just a few days shy of the 28th anniversary of the Labor Day murders, Parabon sent Sergeant Lott two composites. The first one showed an idea of what the suspect looked like back in 1990. And a second one that showed what he might look like now.

Richard Schlesinger: When you look at this picture, what goes through your mind?

Sgt. Bill Lott: Where are you? [smiles] And how am I gonna find you?

But other experts at Parabon were using another method to find the suspect: genetic genealogy.

Dr. Ellen Greytak: In genetic genealogy, we're uploading it to GEDmatch, which is a public database of people who have explicitly chosen to publicly share their DNA for other people to search and have explicitly consented to law enforcement usage.

There are roughly one million people on GEDmatch.com who are searching for family members. The DNA of the Starkville killer was compared to DNA of all those people to see if one of them might be at least a distant relative. And they found something.

Dr. Ellen Greytak: So in this case we were able to find some good matches ... so these are people who genetically match our unknown subject. And we're trying to figure out, based on knowing approximately how much DNA is shared, can we build their family trees and figure out who this unknown person is.

Genetic genealogy helped police catch the alleged Golden State Killer, who is believed to have murdered 13 people and raped 50 women across California in the 1970s and 80s. So Lott hopes it can help him, too.

Sgt. Bill Lott: I've been over obsessed with it, lookin' at it to see if I've got the genetic genealogy yet.

The Jones and Crigler families sensed investigators were on the verge of something big.

"I've just felt an electricity about that this is going to be solved sooner than later," says Juky Crigler Holt, the granddaughter of Kathryn Crigler. CBS News

Juky Crigler Holt: I've just felt an electricity about that this is gonna be solved sooner than later.

And they were right.

David Lindley: I was asleep here at home and about 4am I received a text from Sergeant Lott and he said, "We got him!" ... It wasn't very eloquent, but I believe my exact quote was "you're sh—ing me!"

THE SUSPECT

"KNOCK KNOCK" PODCAST: Over the course of this season, we've unpacked Betty and Kathryn's lives. … We've seen … setbacks and huge opportunities for moving this case forward.

In the summer of 2018, as Jason Jones was completing his podcast series, he was hoping — among other things — that a listener would come forward with information about the murder. A listener did come forward, but with a completely unexpected story.

Jason Jones: We got a message from a girl by the name of Betty Hong. Her story was hard to believe, honestly.

Richard Schlesinger: What was it?

Jason Jones: Betty e-mailed us and let us know that she was actually named for my grandmother.

Betty Hong told Jason that in the '80s, her family — having escaped the brutal Khmer Rouge regime in Cambodia — were sponsored by Betty Jones and several other members of the First Presbyterian Church to come live in Starkville. Betty's mother Kim Hong says her family came to the U.S. with their freedom, but very little else.

Kim Hong: Back then I come, I don't have nothing ... I only have two bag.

Richard Schlesinger: You came with just two bags?

Kim Hong: Two small bag, yeah.

It was before Betty Hong was born, but she says Betty Jones took care of her family and helped them get settled in America.

Betty Hong: She truly impacted my parents' lives directly by clothing them, bringing them out to eat, and did it out of love. And [tearful] we got to come to America and have this American dream. So it's really — Betty Jones is, like, one of those angels that lived upon us ... But now that she's passed, I feel like she's someone who watches over me.

Richard Schlesinger: What is the emotion you're feeling now?

Betty Hong: It's this burst of just — thankfulness.

Betty Hong and Jason Jones meet for the first time. Betty was named for Jason's step-grandmother, Betty Jones. CBS News

In the summer of 2018, "48 Hours" brought Jason and Betty Hong together for the first time.

Betty Hong: We're like family.

Jason Jones: We're totally family, yeah.

The Hong's story became part of the seventh and last episode of the podcast that aired in August 2018. But although the podcast had its finale, it had no finality. Because, still, no one knew who killed Betty and Kathryn.

Jason Jones: What I would hope is that if we did a season two of "Knock Knock," that it would be about the conviction and the trial of the person who killed Betty and Kathryn.

And just weeks after that interview with Jason, it began to look like the story would have the ending he wanted after all. Because, finally, Sgt. Bill Lott had a suspect.

Richard Schlesinger: What was it that led you to this guy?

Sgt. Bill Lott: Genetic genealogy.

Lott's faith in science paid off. A genetic genealogist at Parabon had completed weeks of detailed work building family trees based on those DNA matches on GEDmatch.com, and she gave Lott a name.

Sgt. Bill Lott: It seemed surreal. It didn't — it seemed like I was dreaming ... it wasn't a dream, it was real.

Lott's suspect: 51-year-old Michael Wayne DeVaughn, a twice divorced father of three. He'd worked in construction and farming most of his life. And he was being held in a jail a few hours away on drug charges.

Richard Schlesinger: Why wasn't his DNA in the national database?

Sgt. Bill Lott: He had no prior criminal history until recently ... He's never served time or anything like that. No, he has not.

Lott believed DeVaughn had features similar to the ones depicted in the Parabon composite, but he needed to make sure he had the right man. So he sent a cigarette butt that DeVaughn discarded while in custody on the drug charges to a lab for DNA testing. The result: the DNA on the cigarette was a match to the DNA taken from Kathryn Crigler the night of the attack.

Richard Schlesinger: You went up and got him that day? That Saturday?

Sgt. Bill Lott: Oh yeah … Oh yeah, it was time.

Richard Schlesinger: It was time.

Sgt. Bill Lott: It was time.

On Oct. 6, 2018, 28 years after the crime, Betty and Kathryn's suspected attacker was brought in shackles to Starkville, Mississippi.

On Oct. 6, 2018, 28 years after the crime, Michael DeVaughn was charged with Betty Jones' murder and the rape and sexual battery of Kathryn Crigler. Starkville Police Department

Michael DeVaughn was charged with Betty Jones' murder and the rape and sexual battery of Kathryn Crigler.

Sgt. Bill Lott [choking up at a press conference]: It's been a long, long journey, but I would do it all over again.

And later that day, Lott visited the man who had worked the case first — retired Police Chief David Lindley.

David Lindley: Congratulations!

Sgt. Bill Lott: Congratulations to you. You did a lot of great work. I just finished it.

Betty Jones and Kathryn Crigler Anne McWhorter/Julia Holt

Investigators were finally able to give the victims' families the news they wanted.

Anne McWhorter | Betty Jones' sister: I looked at her picture this morning for the first time in a long time, the tears just flowed down my face ... It was just, "Bet I miss you — even 28 years later."

Richard Schlesinger: Did you think that you would see this day?

Anne McWhorter: No ... You can't believe it because 28 years is a very long time, but there was a bit of excitement there that it's finally done. He's finally been found.

Jason Jones was trying to absorb the news so soon after his podcast's final episode. But his reaction was not as simple as he expected.

Jason Jones: I thought I would feel either happy or mad, but the feelings are a lot more complicated than that ... I feel a sadness towards him that he was a guy that made a series of terrible choices that resulted in taking something away from us that was irreplaceable.

Juky Crigler Holt wasn't quite as understanding.

Juky Crigler Holt: He looked like a man to me that probably had no empathy whatsoever. He could care less about anything he did to anybody … Did I feel sorry for him? [pauses] No.

We may now know who knocked on the door that Labor Day night and attacked Betty.

Jones and Kathryn Crigler. But even if this case has been closed, there are still some questions that remain open.

Jason Jones: Why did this guy choose Betty and Kathryn? What were the circumstances that made him do this? And I know that it won't help, and I know that it won't make anything better, but I think the storyteller in me just needs to know what the end of that story is in order to put it away.

Michael DeVaughn pleaded not quilty in January 2019. He is awaiting trial.

Sergeant Bill Lott has been promoted to lieutenant.