Melbourne mum Maria was murdered 37 years ago. Her case still keeps police up at night.

Ron Iddles, widely regarded as “Australia’s greatest detective” didn’t let many homicide cases escape him.

By the end of a 30-year-long and celebrated career as an Australian detective, 99 per cent of cases Iddles was assigned to were solved, giving closure to families and ensuring the safety of the rest of us.

But for Iddles, despite the accolades and renowned reputation, it’s the one per cent that still occasionally keeps him up at night.

And one of those cases – part of that one per cent – is the 1980 murder of Melbourne mum Maria James.

In the ABC’s newest podcast, Trace, journalist Rachael Brown gives a voice to a case that’s been cold for years, breathing new life and new perspective on an investigation that has stumped Victoria Police for almost four decades.

And Ron Iddles is on hand to help Brown out.

Background:

It was 1980, and Maria James, the mum of two boys, Mark and Adam, owned a bookstore in Thornbury, Melbourne.

On an otherwise average June morning, Maria made her sons breakfast, walked the youngest to school and went back to work. Hours later, she was dead.

It would be these hours, the ones between the school drop off and her brutal death that police, including Iddles - who was assigned to his first ever case - would pore over for years to come.

On June 17, 1980, Maria James' called her ex-husband, John James, with whom she was on good terms with. Although he didn't answer that initial phone call, he called back, only to be put on hold by Maria as she said she had someone with her in the kitchen.

Maria James never picked up the phone again, and John was forced to listen in as his ex-wife had a disagreement with an unknown person. Rushing to the scene of the crime, police believe John James missed his wife's killer by a matter of minutes.

Since then, lead after lead has come up dry, despite the fact police - Iddles included - believe Maria James knew her killer.

“Even though we’re 37 years on, somebody in the community knows who stabbed Maria James,” Iddles told Brown on the ABC podcast.

For Rachael Brown, it's a podcast she wanted to create the moment she began to delve into the case.

“I’ve spent years covering police and court rounds, but for the last couple of years it’s been this case that’s really got its hooks into me.

“Because I heard something on the grape vine that made me suspect something, someone had been overlooked in the original investigation. A piece of evidence, a trace," she says in the podcast.

It's that trace they're chasing, and Australians, much like Brown, are hooked.

Within a day of the first episode's release on Wednesday, Trace jumped to number one on iTunes Australia’s podcast chart.

You can find it here, as Brown investigates the case that has confused Victorians for years.

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