Some Oklahoma murder cases are now getting attention from viewers around the world.

Netflix released a new documentary series Friday called "The Innocent Man," based on John Grisham's book.

Part of the book talks about a Tulsa murder case, involving a man sentenced to death who was later found to be innocent.

"If I wrote ‘The Innocent Man’ as a novel, folks probably wouldn't believe it,” Grisham said in the Netflix trailer.

The six-part series dives into the details surrounding Debbie Carter and Denice Haraway's murders in Ada, back in the '80s. It follows the convictions of four men. Two are in prison, but maintain their innocence.

The other two, including Ron Williamson, were wrongfully convicted.

Part of the trailer shows an exchange with Williamson:

"How close did you come to being executed?”

Williamson: "Five days."

"When you read the book, it's incredible that that could ever happen,” said Betsy Moore of Tulsa.

Moore is Greg Wilhoit's sister. He was wrongfully convicted for his wife's 1985 murder in Tulsa, and sat on death row for nearly five years.

"My brother lost his livelihood. He lost the ability to raise his children. He lost his health physically and mentally,” Moore said. “That should never have happened."

Moore said her brother and Williamson became friends on death row, both insisting they were innocent.

Their families bonded too.

"We just belong to a club that none of us wanted to belong to. And no one else could understand what we've gone through,” Moore said.

"When Ronnie and Dennis Fritz were finally released, my family drove down to Ada.”

While the series doesn't focus on her brother's case, Moore does hope it sheds some light on a scary and painful reality.

"Our hope is that people will realize it can happen to anyone,” she said.

Wilhoit was released in 1993, and told News On 6 then, "I’m just as happy as pie. And I'm just gonna make the best of my new life."

He died in 2014.

"We are a family of deep faith. And we believe this all happened for a higher purpose,” Moore said.

The murder of Wilhoit’s wife, Kathy, is still unsolved.

 

Like many series of the same nature, the shows suggests that there was more to the investigations than the public was originally led to believe. The series features six episodes for Netflix subscribers and true crime fans.