A MOM VANISHES AND NOW HER FIANCé IS IN JAIL AWAITING TRIAL FOR HER MURDER - DOES HIS FORMER RODEO QUEEN GIRLFRIEND HAVE CLUES TO WHAT HAPPENED?

"48 Hours" Investigates in "The Murder of Kelsey Berreth"

Saturday, Oct. 5

Patrick Frazee sits in a Colorado jail awaiting trial for the murder of his fiancé, Kelsey Berreth, who vanished on Thanksgiving Day 2018. As his day in court nears later this month, Frazee is pointing a finger at his once-secret girlfriend, Krystal Lee, a former rodeo queen and nurse, who told authorities she knows how Berreth was killed and why.

Correspondent Nikki Battiste and 48 HOURS take viewers inside the investigation to find out what happened to Berreth and piece together the twisted love triangle that prosecutors say led to the death of the 29-year-old mother in "The Murder of Kelsey Berreth" to be broadcast Saturday, Oct. 5 (10:00 PM, ET/PT) on the CBS Television Network.

It's a story that gripped the country when word surfaced that the engaged mother of a young daughter vanished. It's a case that exposed a secret relationship, problems at home simmering beneath the surface, and wild stories that would lead to a huge break in the case. Berreth's body has never been found.

At the heart of the investigation is Lee, who told investigators Frazee asked her to kill his fiancé with three different plots- though she couldn't go through with it. One of those attempts, Lee told investigators, was a scheme to get Berreth to drink a poisoned caramel macchiato from Starbucks. Prosecutors maintain Frazee ultimately murdered Berreth himself. According to Lee, Frazee told her he killed Berreth with a baseball bat.

"All the clues in the case that investigators are getting are from one person," says Ashley Franco, a reporter for KKTV-TV in Colorado Springs, Colo. "She's the bread and butter to this case. She's the only person in the world that they have to possibly convict Patrick Frazee."

Who is Krystal Lee? Through interviews with friends and more, Battiste and 48 HOURS reveal the mysterious woman behind the heartbreaking case of a family ripped apart by murder and those left behind.

During the investigation into Berreth's disappearance, the FBI got a tip that Lee had confided to her best friend, Michelle Stein, that Frazee sought Lee's help in getting rid of his fiancée.

"She was very, very upset, very distraught," Stein tells Battiste. "She had told me - that he had asked her to take care of his baby mama."

"And so I was like," Stein continues, "Well, I was in shock at first because who says that? Nobody says that - so I was like, what? And she said, 'Yeah, he asked me - if I would kill the mother of his baby.'"

Stein says that she was in shock and disbelief.

"She was bawling. She was crying and extremely upset and scared," Stein says of Lee.

Stein tells Battiste she asked Lee why Frazee wanted to kill Berreth.

"And she said that he had told her it was because she wanted to take him back to court to get custody of the baby," Stein says, "and he was in fear that she was going to harm the baby."

Authorities found no proof Berreth had harmed her daughter, but did find evidence that Frazee had planned to challenge Berreth for custody. They believed that may have been his motive for murder.

48 HOURS: "The Murder of Kelsey Berreth" is produced by Marcelena Spencer. Michael McHugh is the producer/editor. Ryan Smith, Lindsey Schwartz and Cindy Cesare are the development producers. Jen Terker is the associate producer. Grayce Arlotta Berner is the editor. Peter Schweitzer and Gail Zimmerman are the senior producers. Nancy Kramer is the executive story editor. Judy Tygard is the executive producer.

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