Suspicions and secrets revealed in episode 2 of Annette: Cold Case Unlocked podcast

But it doesn't make the 24-year-old any less heartbroken by Annette's suspicious death and the cruel shadow the mystery has cast over her family for almost 40 years.

Nor does it lessen the anger Ms Deverell feels towards authorities who have never held an inquest into Annette's death and never offered a reward for information that might lead to the truth.

"We need justice, we want answers and we want to know," Ms Deverell said.

Speaking after the release of the first episode of the four-part Australian Community Media podcast Annette: Cold Case Unlocked, Ms Deverell hopes renewed interest in the unsolved crime will encourage people with potential clues to come forward.

The first episode, The Skeleton in the Forest, was released on September 11 and was played almost 10,000 times in its first week.

Not just Australians were hooked. The podcast reached the US, UK, New Zealand and Indonesia - hitting No. 1 in Apple Podcast's Australian "top charts" rankings for news content and No. 2 across all categories.

Direct feedback from listeners has included several messages from people who say the podcast has prompted them to provide new information to Crime Stoppers and local police in Mandurah, south of Perth, where Annette spent her teenage years and where she was last seen alive on Saturday September 13, 1980.

LISTEN TO EPISODE 2: right here

LISTEN TO EPISODE 1: right here

Ms Deverell, whose father Michael is one of Annette's three brothers, says it saddens her to think that she never got to know her aunt.

"I really wish I got to meet her," Shae Deverell said. "I wish she was still around so she could see us all grow up."

Annette was 19 when she died. Today she'd be 58, and would have nine nephews and nieces.

Ms Deverell, who has a child of her own, says the loss of Annette had always tormented her father and her grandmother, Margaret Carver, over the years.

She was angry there had never been a reward offered by the Western Australian government for information about Annette's death.

"I think we'll get answers if there is," she said.

"I also think the police could do a much better job than they did last time."

Ms Deverell, like her grandmother and a number of Annette's former high school friends featured in the podcast, suspects that someone who knew her aunt back then - and who is maybe even still living in the town - knows something about how her aunt died, or was directly involved.

Ms Deverell still lives in the Mandurah area.

"You never know, our family could still be talking to them, standing around them and we don't know," she said.

"I hope they're alive to face the consequences - it makes me sick."