'I followed every twist in the "Missing Campers" case. Here's what you don't know.'

Four years ago, Russell Hill, 74, took his mistress Carol Clay, 73, on a camping trip to Wonnangatta Valley. It would be the last place they were seen alive. 

Police spent days searching the campsite for Hill and Clay until they found an abandoned vehicle and belongings, with some items missing. A lengthy investigation began and, eventually, former Jetstar pilot Greg Lynn, 58, became the prime suspect.

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Lynn maintained his innocence, telling the court he had an altercation with Mr Hill which ended with the two men wrestling over Lynn's gun. He claimed his finger was not on the trigger when it went off and shot Carol Clay in the head, killing her.

The former pilot alleged he then snatched the gun and walked away, before Hill approached him with a knife. He said they wrestled once more and tumbled to the ground where Hill allegedly landed on his knife. Hill crawled for a bit, then died, said Lynn. Panicking that no one would believe his story, the 58-year-old decided to make them disappear and disposed of the bodies.

Those were Lynn's version of events to police and to a jury. But there remained many unanswered questions.

It is just the latest of a pattern of mysteries from the camping site, dating back to 1917. And it's a case that piqued the interest of true crime author Robin Bowles. Known for her forensic research skills, the author has penned a thrilling exposé of murder and mystery in the Wonnangatta Valley, called Last Man Standing.

When speaking to the author about the case, we started at the beginning — with Russell and Carol's affair. 

"They were an enigmatic situation," Bowles told Mamamia. "They were lovers. They vanished without a trace."

Watching the media circus from home was Hill's wife of more than 50 years, Robyn Hill, who was well aware of her husband's affair.

"I feel very sorry for Mrs. Hill, who not only lost her husband through all this, but also had to put up with the fact that the media were concentrating very heavily on the fact that they were illicit lovers," Bowles said.

"They had a relationship for a long time, and she actually knew about it; she said in court she knew about it. I suppose she tolerated it. But knowing about something privately and having it as a headline in the paper is not quite the same thing, is it?"

In writing her book, Bowles headed to Wonnangatta Valley to speak to locals and witnesses, including a couple who knew Greg Lynn's estranged wife, Lisa, who was found dead in 1999 outside her home, following an overdose. This became the source of much public speculation as the case unfolded. But the coroner's investigation did not identify any suspicious circumstances involved in Ms Lynn's death.

"I spoke to the couple that were out walking one morning and saw (Lisa's) body in the driveway," Bowles said. "I had a good conversation with them. It made it pretty certain in my mind, and the reasons are in the book, that Lynn was not responsible in any way other than the fact that he left the marriage, and that made her very depressed. But in any other way or shape or form, he wasn't responsible for her death."

Then there was the author's conversation with Harry the back hoe driver, who "nobody thought about interviewing".

"It was Harry's job to sit in the back hoe, up where the remains were found. And every time the forensic people needed more soil, he would come and do another lift of the topsoil and dump it into the strainers that they were using to go through it.

"He was just sitting up there between loads, and all the police were gathered around his back, talking about what had happened and who they interviewed. Some of them were the police that interviewed Lynn and others, so he had all this information directly from the police, and they were talking as if he wasn't there, and telling each other all these very interesting stories.

"Finding those sorts of people, to me, is gold."

This level of research makes sense when you consider the scope of the case, which Bowles says has been "influential in a lot of people's lives".

"It's not like your "normal" murder story by any means. It's taken over people's lives," she told us. "A police officer was in the witness box for four and a half days and he basically stepped out of the witness box, walked up the street and resigned."

Indeed, it was an intense investigation process for the police, who planted listening devices in Lynn's home and put him through a lengthy, and contentious, interrogation.

"The judge felt so strongly about the way that the interview was conducted," said Bowles. "It was nine and a half hours over three days. They had all the legal breaks and everything. They were very careful about that so they weren't seen to be pushing him beyond his abilities. He had cups of tea when he wanted them, and toilet breaks and all that sort of thing. They were all recorded and done by the book.

"But what was not known at the time was that the police were using various techniques that the police do use. It's a bit different from the old telephone book on the sixth floor of the Russell Street police station. That's what they used to use, according to my old copper friends. But they don't use the telephone book anymore. They use psychological approaches and they were on the phone quite often saying, 'Well, that didn't work. Touchy feely stuff isn't getting through to him, what do we try next?'."

When nothing was getting through to Lynn, senior officers made suggestions to "change the tenor of the interview and move him into a different space".

"It was very exhausting for the police, I should think, to conduct that sort of interview over so many days," Bowles said.

"They have basically said that they conducted the interview the way they did because of the relatives, and they needed to close the case and find the bodies for the relatives. They felt that justified pretty much anything that they were doing. And it was nothing to do with getting a result and having spent all this money, it was to make sure the relatives got closure.

"One part of you believes that that's part of their job, in missing persons, is to find people. But the judge was very unimpressed by the questioning, and the Director of Public Prosecutions admitted that it was appalling the way that the police behaved. Well, for prosecutors to say that, I thought that was pretty amazing."

So unimpressed by the actions of the police, the judge initially decided that the jury wouldn't be allowed to hear the interview, or anything consequential from it, in court.

"That meant they couldn't hear how the bones were found — little slivers of bone in the bush, about all that was left of poor Russell and Carol. They weren't allowed to hear any of that. So any evidence from police or forensic people who attended the dig. That was a pretty unusual ruling from his honour, very unusual."

The DPP, however, argued for the inclusion of the evidence.

"He stood up and he said, 'Your Honor, if you rule that out, I don't have a case.' And his honour said. 'Well, you better go out and think about that'."

Greg Lynn. Image: Facebook.

Eventually, the judge's decision was appealed — just another twist in this already unorthodox case. 

"I looked back through all the annual reports, and they sometimes appeal the sentence, and they sometimes appeal the finding guilty or not guilty, but I couldn't find one where they actually appealed a judge's decision to let something in or not."

It was at the appeal court that Bowles would overhear a defining interaction.

"One of the appeal judges said to the other 'Well, this case will make a question on a legal honours paper, I'm sure.' And the other person said, 'Well, I don't know. It's not all quite complicated, really. Three people went camping, only one came back. Last man standing."

While those three words seemed an obvious title for her book, the six-week trial wasn't quite so easy.

The author attended every day, watching as the prosecution and defence took the stand in turn.

"Hearing the victim impact statements read out was also very impactful," she said. "They were beautifully written and really beautifully delivered. I think they had a big impact on the judge. When he was mentioning them during his sentencing remarks, he was in tears."

Lynn, however, made a convincing case.

"He gave evidence in the court. Murder defendants rarely give evidence on their own behalf, because they open themselves up to pretty nasty prosecution questions," she explained.

"But in Mr. Lynn's case, he decided to give evidence. He was a good witness. He told his story in a very straightforward way, and he was believable. I find that the prosecution's case was not very well made, to be honest."

Jurors certainly had their doubts too, deliberating for more than a week. It came down to one question: had Greg Lynn, beyond reasonable doubt, murdered Russell Hill and Carol Clay?

In the end, the jury found Lynn guilty of murdering Clay, but not guilty of murdering Hill.

Four months later, the former pilot heard his sentence — 32 years in jail, with an opportunity for parole after 24 years.

Bowles remembers vividly the moment the verdict was delivered.

"When they came back with 'not guilty' for Russell's death, there was this atmosphere in the court where everyone was holding their breath. It was a really strange feeling to be there," Bowles recalled.

"It was sort of a collective of 'what now?'. They came back with the guilty verdict, and I was looking at (Lynn), and all he did was raise one eyebrow. He didn't move, he did nothing, no facial expression whatsoever. Seeing poor young Geordie (Lynn's son) after the verdict was delivered, he was shattered," she said. 

"Everyone else had an expression of a wet blanket being thrown over something. That's what it was like. Nobody spoke. It was total silence, which was really weird. People seemed to feel like they didn't know what to do now, they didn't want to hang around but, but they also wanted to talk to someone about it."

Despite Lynn receiving his sentence, Bowles is sure the story isn't over. 

"He'll appeal," she asserted. "And there's a chance he could get off because the jury really didn't deliver a verdict that was in line with the judge's direction."

So with the lingering questions about this case, and the many other mysteries of Wonnangatta Valley, where do we go from here?

"Don't go camping in the high country," Bowles said. "It's a beautiful place, and it does get under your skin a bit. But I think if you're going up there, go back home and sleep somewhere safe every night. Because, you know, strange things do happen to people who go up there and go out on their own and they're camping, 

"There are disappearances that are still not solved. You never know, there might be somebody out there making people disappear."

You can buy Last Man Standing here.

Feature image: Victoria Police.