Nearly fifty years later, could this case still be solved — and on what evidence?

Before any explanation can be tested, the reliability of the evidence must be established.

In the decades since Denise McGregor was murdered, technology has advanced — but the evidence itself has not stood still.

Some material remains. Some has been lost. Some can no longer be interpreted with certainty.

This episode establishes the boundaries.

It examines what evidence from 1978 can still be relied upon, what has degraded or changed over time, and where the limits of modern analysis now lie — including the role of emerging tools such as AI.

This is not about suspects or conclusions.

It is about what can safely support them.

Because once information is mishandled, it cannot be undone.

And any explanation that follows must be grounded in evidence that can still bear weight.

Content warning: This series discusses the sexual assault and murder of a child. Clinical, non-graphic language throughout. Listener discretion advised.

If you have information, contact Victoria Police Crime Stoppers: 1800 333 000 or www.police.vic.gov.au/crime-stoppers