At 6am, the body of Wilhelmina Kruger - a 57-year-old cleaner at the Piccadilly Arcade - was found at the foot of the stairs to the lower parking area of the centre.

Her body was in such a state that a Sydney detective sergeant brought down to take charge of the case called it “one of the most vicious in the history of this state”.

Police believed she was first attacked at the top of the escalators in the Piccadilly Centre.

A trail of blood, clothing and other items down the escalator and a set of stairs showed the killer had then dragged her - while she was possibly still alive - down two flights before brutally killing her.

READ MORE: Wollongong’s unsolved cases

Despite the best efforts of police at the time - and a later possibility of using DNA evidence - Wilhelmina’s killer has never been found.

The case has now drawn the interest of two Wollongong women, who are planning to make a documentary about Wilhelmina and her murder.

Josie Stuart and Katie Huggins have started up IE Works to make the film about Wilhelmina as well as a podcast looking at the secret, strange history of the city.

Ms Stuart said she was drawn to Wilhelmina’s story as soon as she heard about the case.

“I think because the Piccadilly Centre is such a strange place to be but also it was the kind of mythology her murder has brought up in people,” Ms Stuart said.

“There are so many different versions about what happened to her.”

Work has started on the film but Ms Stuart said talking to the family was a “real priority”.

“We’ve done quite a bit of research [and] our main goal at the moment is to contact Wilhelmina Kruger’s family because we want their go-ahead and we want to know their side of the story,” she said.

“We were on the radio and someone who knew one of her sons is trying to point us in the right direction to get in contact with them.”

Anyone with information about the case or contact details for Wilhelmina’s family can contact Ms Stuart via the I.E Works (@IdEstWorks) Facebook page.