"48 HOURS" FEATURES TWO MOMS WHO HELPED POLICE CRACK THE MORE THAN TWO-DECADE-OLD COLD CASE OF A COLLEGE STUDENT MURDERED ON THANKSGIVING WEEKEND

"48 Hours" Investigates in "Mandy Stavik: The Case No One Could Forget"

Saturday, Nov. 30

Correspondent Peter Van Sant and 48 HOURS investigate the more than two-decade-old cold case of a college student murdered on Thanksgiving weekend in 1989 in "Mandy Stavik: The Case No One Could Forget," to be broadcast Saturday, Nov. 30 (10:00 PM, ET/PT) on the CBS Television Network.

The broadcast features the first network television interviews with two mothers who helped police crack open the case. 48 HOURS also goes inside the investigation with a coworker of the alleged killer who delivered the key evidence that investigators needed to make an arrest.

The Stavik murder was seemingly unsolvable and hung over the small tight-knit community of Acme, Wash., like a dark cloud for decades. Stavik was just 18 when she disappeared after going out for a run. Her body was found three days later in the Nooksack River. Investigators believed she had been sexually assaulted, knocked out and placed in the river to drown.

"She was just floating lightly when I rolled her over it was kind of - a real shock to me because she looked like my daughter," says Ron Peterson, then a Whatcom County Sheriff's Department detective when he found her body.

Despite having DNA evidence and an intensive police investigation, the suspect was unknown for 24 years. That is, until 2013, when two mothers, Merrilee Anderson and Heather Backstrom, were chatting with other mothers while their kids played at a waterpark. The conversation shifted to the Stavik murder.

"And I just kind of turned to Merrilee and said, 'Well, I am sure I know who killed her," Backstrom says.

"And I turned to her and said, 'Oh, I do, too," Anderson says. "And I just said I knew that it was Tim Bass."

Bass had lived just down the road from Stavik. Anderson and Backstrom had creepy encounters with him around the time of Stavik's murder, but they had never come forward with their suspicions.

"To accuse someone of something that we don't know for sure is a little scary," Anderson says.

However, after hearing each other's stories, Anderson decided to talk to police. Bass was, by then, married and working as a driver at a bakery. Police began investigating Bass, and turned to the assistance of Kim Wagner, a co-worker at the bakery where he worked. Wagner came up with a plan to help police get the DNA they needed to connect Bass to the crime.

"I just never forgot about Mandy," Wagner says. "And that's why I did it."

48 HOURS: "Mandy Stavik: The Case No One Could Forget" features interviews with investigators, Bass' ex-wife, his attorneys, Stavik's mother and more. 48 HOURS: "Mandy Stavik: The Case No One Could Forget" is produced by Alec Sirken and Emily Wichick. Greg Fisher is the development producer. Ken Blum is the producer-editor. Phil Tangel is the editor. Lourdes Aguiar is the senior producer. Nancy Kramer is the executive story editor. Judy Tygard is the executive producer.

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