It has been thirty-five years since two sisters were murdered after leaving the Oklahoma State Fair.
Investigators say it is the most infamous cold case in Oklahoma history.
Investigators say Sept. 23, 1987 was the last time the sisters were seen alive.
They were at the state fair that night but it is still a mystery what happened after they left.
25-year-old Cheryl Gezner and 16-year-old Lisa Pennington were murdered after leaving the state fair 35 years ago.
"I remember both of them had beautiful smiles," brother Alan Pennington said. "Both were flamboyant. They enjoyed music and enjoyed life. They were still so young."
Their bodies were found buried in a shallow grave in Oklahoma City a month after they disappeared.
"They left with two guys and they were alive and well when they left," former private investigator Dorian Quillen said. "They went to this guy's house in the suburb of the city called Britton and they were never seen again by anyone who knew them."
One man was arrested for the killings but the charges were dropped.
"We believe there may have been a sexual assault that night and one of the girls saw it and began fighting on behalf of her sister and things got out of hand," Quillen said. "That is the story we understand."
Friends believe one of the killers is dead and say the other man they believe is responsible still brags about it.
"If someone wants to take credit for this, it is time we start believing them," Quillen said. "It has been 35 years and they need to start looking into it instead of saying that it is just hearsay."
Cheryl and Lisa are now buried at a Geary cemetery next to their parents an family hopes this case is solved soon.
"We know somebody knows something," Pennington said. "It is time somebody steps forward and we get some type of closure to this case."
The family wants police to take another look at this case and investigators say any tip can help solve it.
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