Woman Who Dated 'Hillside Strangler' Serial Killer Speaks Out: 'I Was in Denial'

Mar. 15, 2025

Ken Bianchi and Angelo Buono.Photo: shutterstock (2)

It was the late 1970s in Southern California. Seventeen-year-old Sheryl Kellison and her friend, Lisa, were driving around carefree in the Los Angeles suburb of Eagle Rock when a Chevy Impala with four men inside pulled up next to them.

The two began dating.

“He’d have dinner with us,” she says. “My dad was very ill and in and out of the hospital and he would go to the hospital, and he would shave my dad and feed him.”

Kellison says she had no idea that the man she dated on and off for almost three years was a serial killer, who, along with his cousin, Angelo Buono, were responsible for 10 murders of women and girls. The murders became known as the “Hillside Strangler” killings, occurring during a four-month period between October 1977 and February 1978.

“Never in my wildest dreams would I think it was him,” Kellison says. “He was sweet to me.”

The killings are the focus of a new true crime series,The Hillside Strangler: Devil in Disguise, premiering Aug. 2 on Peacock.

The series features video and audio tapes of psychiatric and police interviews of Bianchi while he was in custody as well as exclusive interviews with Kellison.

‘In Denial’ After Bianchi’s Arrest

During that period, law enforcement received thousands of tips, including one from Kellison’s mother.

“She had a gut feeling” about Bianchi, says Kellison, who says her mother never told her about her suspicions. “[Police] went and checked him out, and they came back and told her, ‘Mrs. Kellison, you have nothing to worry about. He checked out just fine.’ He turned on the charm. He conned the cops.”

“There might have been a little bit of sexism involved, maybe more than a little, in the way that some of these tips were handled,” says director Alexa Danner. “The police may have thought that Sheryl’s mother was an over-reactive woman. They didn’t have any clear evidence to tie Ken to the killings other than a handful of suspicions.”

But all that changed on January 12, 1979, when Bianchi, then 27, was arrested for the strangulation murders of college students Diane Wilder and Karen Mandic in Washington State.

Kellison remembers the day when Los Angeles police showed up at her parents' home to tell her about Bianchi’s arrest.

“I was in denial,” she says.

Hillside Strangler victims Yolanda Washington, Judith Miller, Lissa Kastin, Delores Cepeda, Sonja Johnson, Kristina Weckler, Evelyn Jane King, Lauren Wagner, Kimberly Martin and Cindy Hudspeth.IMDB

However, the more she thought about it the more “it started to make more sense.”

She remembers driving Bianchi to a cemetery for a job interview but once there, he decided he didn’t want the job. “A week later, one of the bodies was found out there,” she says. “He was just looking for a place to leave his next victim.”

Who Was the Mastermind?

Bianchi, she says, looked up to Buono, who was 17 years his senior. “He just followed him around and did whatever he wanted him to do. And I felt like Ken was just his little sheep.”

But the question of who the ringleader was behind the slayings is up for debate, says director Alexa Danner.

“Some people believe that Angelo was this quiet, dark mastermind who was puppetting Ken Bianchi, and other people believe the opposite that Ken was actually the one driving everything,” she says. “I think the only people who know the real truth are Ken Bianchi and Angelo Buono.”

Bianchi confessed and then denied involvement in the slayings, eventually agreeing to a plea deal to avoid the death penalty in exchange for testifying against Buono.

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“One of the things that’s really compelling, but also confounding, about Ken Bianchi is his ability to be such a chameleon,” says Danner. “It’s hard to know with Ken Bianchi what’s the truth and what is not. And I think that’s one of the core questions at the heart of this case.”

Buono was convicted of nine of the 10 killings in 1983 and sentenced to life in prison without the possibility of parole. He died of natural causes in 2002 at the age of 67.

Bianchi, now 71, is serving a life sentence in Washington State.

For Kellison, she feels lucky she didn’t become a victim of the duo and believes she was saved because of Bianchi’s close relationship with her parents.

“He didn’t want to hurt them,” she says. “That’s the only reason I’m still here.”

The Hillside Strangler: Devil in Disguisepremieres August 2 on Peacock.

source: people.com