Peacock's The Hillside Strangler Goes Inside the Minds of Killer Cousins in Chilling First Look

Horror in the hills of Los Angeles.

E! News has the chilling first look at Peacock's new true crime special, The Hillside Strangler: Devil in Disguise. The four-part docu-series—which premieres Aug. 2—will re-examine the terrifying story of notorious serial killing cousins Kenneth Bianchi and Angelo Buono Jr. who murdered nearly a dozen L.A. area women in the 1970s.

"In Los Angeles, somebody or a team has been murdering girls—lots of them," a decades-old news report declares in the trailer.

Soon, tension swept through Los Angeles.

"Everybody was really on edge and worried," Dr. Lois Lee, founder of the anti-sex trafficking charity Children of the Night, adds. "They could be next."

The preview teases an in-depth look at Bianchi's arrest and subsequent claim that he had multiple personalities.

"If he had multiple personalities, why didn't I ever see one?" Bianchi's former girlfriend, Sheryl Kellison, questions in the clip.

But law enforcement officials quickly began to question Bianchi's story.

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As one investigator put it: "There was never any doubt in my mind that there was at least two suspects. I wonder where the other guy is?"

After leaving many dead bodies around the hills outside L.A., Bianchi and Buono Jr. were eventually convicted of kidnapping, raping and murdering 10 women.

Check out the chilling first look above.

The Hillside Strangler: Devil in Disguise premieres Aug. 2 on Peacock.

(E! and Peacock are both part of the NBCUniversal family)

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