Two 18-year-old girls disappeared on the Flinders Highway in 1972. One was found murdered, the other has never been found. In this first episode of our special series for Outback Murder Highway, Tim &amp; Xanthe are joined by investigative journalist Amelia Oberhardt to dissect the unsolved case of Anita Cunningham and Robin Hoinville-Bartram. Could police have missed crucial evidence all those years ago that could prove&nbsp; they were victims of one of Australia's most notorious serial killers? <hr> You can watch the Outback Murder Highway TV documentary series 8.30pm Wednesday on Channel 9&nbsp; from April 22 to May 13. <a href="https://www.9now.com.au/outback-murder-highway">Or watch anytime here - on 9Now. </a>See <a href="https://omnystudio.com/listener">omnystudio.com/listener</a> for privacy information.

Bonus: David Cunningham [Extended Interview]

Motive &amp; Method is an expert-led Australian true crime podcast. Join Dr Xanthe Mallett and criminal psychologist Tim Watson-Munro as they unpack what really makes the offenders behind some of history’s most notorious cases tick, and also react and unpack crimes as they hit the headlines. You will also hear from victim survivors, investigators and advocates for change analysing motive, and method.