CAN A DRIVEN DETECTIVE AND CUTTING-EDGE TECHNOLOGY SOLVE A NEARLY THREE-DECADE-OLD DOUBLE MURDER SPOTLIGHTED IN A PODCAST?

"48 Hours" Investigates in "Knock Knock"

Saturday, Jan. 19 (10:00 PM, ET/PT)

Can a driven detective and cutting-edge technology solve a nearly three-decade-old double murder? 48 HOURS and correspondent Richard Schlesinger go inside the investigation into the murders of two beloved grandmothers in "Knock Knock," to be broadcast Saturday, Jan. 19 (10:00 PM, ET/PT) on the CBS Television Network.

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 tells 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," says Lott.

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

"It's like, now I know what you look like," says Lott. "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?

48 HOURS: "Knock Knock" is produced by Lourdes Aguiar. Stephen A. McCain is the development producer. Jordan Kinsey is the associate producer. Michael McHugh, Gregory F. McLaughlin and Jason Schmidt are the editors. Peter Schweitzer is the senior producer. Nancy Kramer is the executive story editor. Judy Tygard is the executive producer.

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