An Oregon Mom and Her 6-Year-Old Twins Were Found Brutally Murdered — But Who Wanted Them Dead?

A new episode of A&E’s 'Secrets of Hells Angels' takes viewers on a detective’s 18-year quest to find their killers

What gained the detective’s attention about the confidential informant’s account of how an Oregon mother and her 6-year-old twins were killed was one small detail: One of the girls was clutching a toy from a Cracker Jack box when she was shot in the head.

The killings occurred on Aug. 7, 1977. For years, Detective Sergeant Mike Graham had been looking for the people responsible for the execution-style murders of Margo Compton, 24, and her twin daughters, Sylvia and Sandra, as well as her boyfriend’s 19-year-old son, Gary Seslar.

A new episode of the eight-part series Secrets of the Hells Angels follows the detective’s 18-year journey to uncover the mysterious killers responsible for the four deaths and airs Sunday at 10 p.m. ET/PT on A&E. (Watch an exclusive clip below.)

“I had withheld a little bit of evidence from the public,” Graham says of the Cracker Jack toy detail in the upcoming episode of Secrets of the Hells Angels, adding: “And Michael [Thompson] knew it. That's when I knew that Michael was telling me the truth.”

Graham was referring to “Iron Mike” Thompson, then a leader of the Aryan Brotherhood prison gang, who met with the detective in 1984.

Related: Undercover Female Agent Recalls Infiltrating Infamous Biker Gang: ‘We're All Just Property of the Hells Angels’

At the time, the White supremacist gang ran methamphetamine sales inside California prisons, while the Hells Angels ran the market on the streets. Often, incarcerated bikers joined the prison gang.

It was behind bars where, Odis “Buck” Garrett, a major meth supplier in prison, had told Thompson the story of the family’s infamous murders — and Thompson started sharing those secrets with the detective.

Recalling their early meetings, Thompson tells A&E that Graham was “very direct” and uninterested in cutting him a deal in exchange for testimony.

“‘Look, I don't really care about you, but I have a passion and my passion is to come to terms with the execution of these two little girls and Margo Compton,” Thompson recalls Graham saying. “And I said, ‘Well, we share that.’”

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While the two men were incarcerated at Folsom State Penitentiary in the late 1970s, Thompson had declined Garrett's business proposal, saying he was uninterested in working with child killers. (Rumors had spread that Garrett was responsible for killing the young twins.)

Eventually, Garrett — a leader of the Hells Angels Vallejo chapter — told him that while he ordered the slayings, the man who had pulled the trigger was Robert G. “Bugeye” McClure, a Hells Angels "hang-around," meaning someone who spends time with group members but isn't yet part of the organization.

Thompson reported back to the authorities.

That was the “huge break in the case” that the detective had been looking for — one that connected the murders to the Hells Angeles, Graham tells A&E in the hour-long episode which includes first-ever interviews with family members and eyewitnesses in the case.

Compton, a young mother of rural Gaston, Ore., had previously testified against several Hells Angels members at a prostitution trial in San Francisco, making her the target of retaliation,The New York Times later reported from McClure’s 1994 murder trial.

Following his conviction in the prostitution case, Garrett had ordered McClure to kill Compton and her family members, The Times reported from the courtroom.

At the time, Judge Jon B. Lund called the murder case one of the “most egregious” ones he had ever come across, per The Times, telling McClure that he had been “heartless and coldblooded” to kill “four innocent people.”

The July 1994 trial included testimony from more than 75 witnesses, per The Times, which noted that many of the Hells Angels and Aryan Brotherhood members entered the courtroom shackled in leg irons and waist chains as well as handcuffs.

At the trial, one such prisoner said McClure boasted to him that he had forced Compton to watch as he first killed her daughters, adding that the little girls died clutching their teddy bears, per The Times.

Convicted of their murders, McClure was sentenced to four consecutive life terms in prison.

A year later, Garrett was convicted of the four killings and received the same sentence.

New episodes of Secrets of the Hells Angels air Sundays at 10 p.m. ET/ PT on A&E.

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