The discovery of the body of Beth Barnard in her Phillip Island farmhouse in 1986, began a homicide investigation that rocked a peaceful community.

It also created an enduring mystery, for no one was ever brought to trial for her brutal death, and the main suspect disappeared - never to be seen again.

Beth Barnard, a popular and attractive 23-year-old, had been having an affair with a local married man.

On the night of her brutal murder, a car belonging to Vivienne Cameron - wife of Beth's lover - was found abandoned near the bridge that connects the famous tourist island to the mainland.

No trace of Vivienne was ever found, and her disappearance has never been adequately explained.

Nevertheless, a Coroner's Court found that Vivienne had killed her rival then jumped to her death into the waters of Westernport Bay. The case was closed but not forgotten.

Ever since their first edition of The Phillip Island Murder, in 1993, Vikki Petraitis and Paul Daley have been regularly contacted by people wanting to know more; people who, like the authors, let the case get under their skin.

More than three decades later the mystery, rumours and arm-chair solutions continue.