ONE of the Northern Rivers' greatest mysteries - the murder of Lismore woman Lois Roberts - will be explored during a TV documentary that airs tonight.
In July 1998 Lois was hitch-hiking from Nimbin to Lismore when a witness saw her get into a white car.
The 38-year-old was never seen alive again.
Six months later a bushwalker stumbled across Lois' body, which was bound in electrical cord, under leaf litter in the Whian Whian State Conservation Area.
Police believe she was held captive and kept alive for around 10 days, during which time she was tortured and sexually abused before being killed.
Cold Justice, a documentary that will air on NITV tonight, will detail the three main theories surrounding Lois' death.
The first is that she was killed by a man who was "infatuated with Lois' identical twin sister Rhoda Roberts".
The second theory is that Lois was the victim of a serial killer who targeted women around the Northern Rivers in the late 1990s.
The third is that "Lois was murdered because she was about to expose a pedophile ring operating in Lismore".
Host of Cold Justice, Allan Clarke, said investigating Lois' death for the show was a difficult task, and that many people were reluctant to speak on camera.
He said the story was not just about the murder, but about her family's extraordinary fight to ensure Lois' death was not in vain.
Rhoda Roberts, as well as Lois' brothers Phil and Mark Roberts and nephew Gilbert Laurie, were interviewed for tonight's show, along with Nimbin locals and some of Lois' friends.
Watch Cold Justice on NITV tonight at 9pm.
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