Hollywood in the late seventies wasn't just about disco and neon lights. It was a place of genuine, bone-chilling terror. Between October 1977 and February 1978, a shadow fell over Los Angeles that the media quickly labeled the work of the "Hillside Strangler." But the moniker was wrong. It wasn't one man. It was two. Angelo Buono and Kenneth Bianchi, a pair of cousins with a relationship so toxic it fueled a five-month descent into absolute depravity.
Honestly, when you look at the case now, it’s the sheer audacity of these two that sticks with you. They weren't hiding in the bushes like movie monsters. They were hiding in plain sight. They used fake badges to impersonate police officers, a trick that turned the very people society is supposed to trust into a death trap.
The Partnership From Hell
Kenneth Bianchi moved from Rochester to LA in 1976. He wanted a fresh start, or so he said. He moved in with his cousin, Angelo Buono. Buono was older, a guy who ran an upholstery shop in Glendale and had a rap sheet that would make your skin crawl—mostly involving violence against women.
They weren't just relatives; they were a catalyst for each other’s worst impulses.
The killing didn't start immediately. First, they tried their hand at pimping. They even bought a "trick list" from a woman named Yolanda Washington, but when the list turned out to be a dud, they didn't just get mad. They got murderous. On October 17, 1977, Yolanda Washington became their first victim. They raped her in the back of a car and strangled her.
✨ Don't miss: The CIA Stars on the Wall: What the Memorial Really Represents
That was the spark. Over the next few months, ten women and girls—some as young as twelve—were abducted, tortured at Buono’s shop, and dumped on the hillsides of LA.
Why the Police Missed Them for So Long
You’ve gotta realize how chaotic LA was back then. The LAPD was overwhelmed. Plus, Bianchi was a master of "blending in." Get this: while he was out murdering women at night, he was literally applying for a job with the LAPD during the day. He even went on police ride-alongs. Imagine sitting in a patrol car, chatting with cops about a serial killer, knowing full well you’re the guy they’re looking for. It's the kind of detail that sounds like bad fiction, but it was 100% real.
The duo was meticulous, too. They’d clean the bodies to remove forensic evidence before dumping them. In 1977, DNA testing wasn't a thing yet. Investigators were looking for a lone wolf, not a tag-team of cousins who went home to a "normal" upholstery business after a night of horror.
The Fake Multiple Personalities
The house of cards finally fell when Bianchi moved to Washington State. He couldn't stop. He killed two more women in Bellingham, and this time, the trail led straight to him.
🔗 Read more: Passive Resistance Explained: Why It Is Way More Than Just Standing Still
Once he was cornered, Bianchi tried one of the most famous—and failed—legal gambits in history. He claimed he had Dissociative Identity Disorder (what people used to call multiple personalities). He said a "bad" alter named "Steve Walker" was the one who committed the murders.
- The Hypnosis: Experts like Dr. John Watkins initially believed him.
- The Exposure: Dr. Martin Orne, a world-renowned hypnosis expert, wasn't buying it. He did a "double hallucination" test. He told a "hypnotized" Bianchi that his lawyer was in the room (when he wasn't) and then had the actual lawyer walk in. A real person in a trance would usually "see" both and not be bothered. Bianchi got confused. He was faking.
Basically, Kenneth Bianchi was just a very good liar who realized he was facing the death penalty. To save his own neck, he eventually dropped the act and pointed the finger at his cousin, Angelo Buono and Kenneth Bianchi became household names during the trial that followed.
A Trial That Broke Records
The trial of Angelo Buono was a marathon. It started in 1981 and didn't wrap up until late 1983. At the time, it was the longest murder trial in U.S. history.
Buono was a piece of work. Even with Bianchi testifying against him, he maintained he was an innocent upholsterer who'd been framed. The prosecution had to rely on tiny bits of physical evidence—fibers from the upholstery shop found on the victims—and the testimony of women who had escaped Buono’s earlier abuses.
💡 You might also like: What Really Happened With the Women's Orchestra of Auschwitz
Ultimately, the jury didn't buy Buono's "innocent businessman" act. He was convicted of nine murders. He died in prison in 2002 from a heart attack. Bianchi is still sitting in a cell in Washington, denied parole as recently as 2025 because, frankly, the guy is still considered a massive risk.
What We Learn From the Hillside Strangler Case
The legacy of Angelo Buono and Kenneth Bianchi isn't just about the crimes; it's about how they changed investigative psychology and police work.
- Trust Your Gut, But Verify: The fact that Bianchi was doing ride-alongs shows that killers don't always look like "creeps." They can be the guy next door or the guy trying to join the force.
- The "Shared Psychosis" Factor: Psychologists often point to this case when discussing folie à deux. Neither of these men might have become serial killers on their own, but together, they created a feedback loop of violence.
- The Limits of Malingering: Bianchi’s failed attempt to fake a mental illness remains a landmark case for forensic psychologists in spotting "malingering" or faking symptoms for legal gain.
If you’re interested in the darker side of American history, looking into the specific victim advocacy that arose after this case is a solid next step. Many of the victims’ families became vocal supporters of better missing persons protocols, which was a direct response to how slowly the initial investigation moved. You might also want to look into the "California v. Buono" court transcripts if you want to see exactly how the fiber evidence—groundbreaking for its time—was used to link the upholstery shop to the hillsides.
The Hillside Strangler story is finished, but its impact on how we understand criminal partnerships and the "mask of sanity" is something experts are still picking apart today. There's no mystery left about who did it, only a lingering chill when you realize how easily they moved among us.
To get a better sense of the atmosphere in 1970s LA, research the LAPD’s "Task Force" files from 1978. It shows just how much the city was on edge before the cousins were finally unmasked.