Serial killer Kenneth Bianchi and his cousin Angelo Buono left a path of death in Los Angeles and Washington in the late 1970s. 

By the time he was caught in 1979, convicted serial killer Kenneth Bianchi’s heinous homicidal spree across late-1970s Los Angeles had been given a chilling name: the Hillside Stranglings.

For four agonizing months beginning in October 1977, teenage girls and young women began turning up dead around the city. Some of them were tortured and sexually assaulted before being strangled to death and dumped in hilly areas. 

“The Hillside Strangler: Devil in Disguise,” a four-part Peacock docuseries premiering Tuesday, August 2, offers a fresh look into the notorious slayings, as well as into the persona of Bianchi, one of the convicted serial killers behind them. 

Comprised of interviews with investigators who worked the case and the killer’s ex-girlfriend, amongst others, as well as video and audio recordings of Bianchi’s psychological analysis sessions, the docuseries offers a fresh perspective on a depraved and deadly individual.

A troubled youth who was born in 1951 and raised by adoptive parents in Rochester, New York, Bianchi moved to California after high school, following failed efforts to land work in law enforcement.  Upon arriving in Los Angeles, he lived with his adoptive cousin Angelo Buono. Buono would later be implicated in the murders while Bianchi was undergoing psychiatric evaluations, as seen in “Devil In Disguise: The Hillside Strangler.”  According to investigators, Bianchi and Buono posed as police to lure their victims in L.A. until Bianchi moved to Washington.

Bianchi was arrested on January 12, 1979, by Bellingham police for the murder of Washington University students Karen L. Mandic and Diane A. Wilder. 

While in custody for the Bellingham double homicide, Bianchi was linked by law enforcement to the unsolved Hillside Stranglings in L.A.

Bianchi insisted he had dissociative identity disorder  , which was known at the time as multiple personality disorder, and that his other personalities were responsible for the killings, claims that were later questioned by experts.

Bianchi later abandoned this defense and pleaded guilty to the Washington double murder and five of the L.A. slayings, according to the St. Louis Post-Dispatch. He was sentenced to multiple life terms and remains incarcerated in the Washington State Penitentiary in Walla Walla.

As for Buono, he was arrested in October 1979 after Bianchi pointed the finger at him as an accomplice. He was convicted of nine of the 10 murders and sentenced to life behind bars, the St. Louis Post-Dispatch reported. Buono died in prison in 2002.

To learn more about the case, watch Peacock’s “The Hillside Strangler: Devil In Disguise,” premiering on August 2.

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