It was January 16, 2001, when British backpackers Peter Falconio and Joanne Lees, touched down in sunny Sydney, Australia.

The couple, from Hepworth, West Yorkshire, had already travelled around Nepal, Singapore, Thailand, Cambodia and Malaysia.

Australia was to be the final leg of their round the world trip.

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But their parents were worried about it. The Land Down Under had been making headlines for all the wrong reasons; recent news of serial killer Ivan Milat’s backpacker victims, the Port Arthur killings and the Childers Palace Backpackers hostel fire had made them anxious.

Despite this, Peter, 28, and Joanne, 27, were excited, promising their parents they would be careful.

Like hundreds of thousands of young travellers before them, they decided to settle in Sydney for a few months while they worked and saved money, before embarking on an epic road trip from Sydney to Melbourne, Adelaide, Darwin and Brisbane.

Peter found work installing office furniture while Joanne got a job in the Dymocks book store on George Street, in the CBD.

By the end of June, they decided they’d saved enough cash. The couple purchased a 30-year-old, orange VW Kombi van for $1800 and set off.

On July 14, 2001, the couple had reached Alice Springs where they watched the "Camel Cup", a unique outback spectacle where locals and tourists watch camels, rather than horses, race along a dusty course. Afterwards, they continued their journey north up the Stuart Highway, bound for the Devil's Marbles.

At 6.20 p.m., they stopped in Ti Tree, bought fuel, watched the sunset and shared a joint.

Another 100km north, Peter was driving and Joanne was sitting in the passenger seat. As they passed through the blink-and-you'll-miss-it town of Barrow Creek, they noticed headlights in their rearview mirror.

A man in a white Toyota four-wheel drive with a green canvas canopy drew up alongside them and gestured to them to pull over.

Peter did just that and went to speak to the man, who said he'd seen sparks coming from their exhaust pipe.

Joanne Lees would later explain that as the two men went to the rear of the vehicle to check it out, she moved into the driver's seat, ready to rev the engine.

Then, she heard a loud bang.

"At first it just sounded like a car backfiring, but it also sounded like a gunshot," she would later tell a court.

The man then appeared at the window of the Kombi and pointed a gun at her head.

"I just kept thinking, this was not happening to me. I couldn't believe that this was happening. I felt alone. I kept shouting for Pete and thought I was going to die," she recalled.

"I was more scared of being raped than being shot by the man," she said.

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It was only then, Joanne said, that she realised Peter might have been shot.

Desperately, she tried to escape, but the man with the gun grappled with her, eventually tying her hands behind her back with homemade cuffs fashioned from cable ties and masking tape.

Joanne kicked and screamed as he tried to bind her ankles.

Eventually, the man gave up with the ankle ties. Instead, he punched her hard in the side of her head, then dragged her to the rear of his vehicle and dumped her in the tray.

Then, he went back outside. Joanne could hear scraping and dragging. She was absolutely terrified, but as the sounds became more distant she managed to roll out of the vehicle, run away and hide in the bushes where she remained for five hours, as the man searched for her by torchlight, until she was able to flag down a passing road train.

She was driven back to Barrow Creek where she called the police.

They immediately began an investigation, searching the vast bushland for Peter and the unknown gunman. When they returned to the scene of the crime, they found a dirt-covered blood pool and the couple's Kombi hidden some 80 metres into the scrub.

But while police searched for a killer, some were beginning to doubt Joanne's version of events.

A press conference was held 11 days after the attack and while answering questions about her boyfriend's suspected murder, Joanne wore a singlet with the words 'Cheeky Monkey' emblazoned across the chest.

A tasteless choice, many thought.

She also appeared emotionless, refusing to cry on cue.

Comparisons were made to Lindy Chamberlain, who was jailed in 1982 for the murder of her baby daughter Azaria in August 1980, only for an inquest in 2012 to declare a dingo took her baby.

People had said she was cold and unfeeling too.

Joanne was also accused of being 'bolshy' towards the media, allowing only one reporter to ask her a total of three pre-prepared questions.

Perhaps fuelled by media speculation that she wasn't telling the whole truth, police hauled her in.

The night before she was due to leave Alice Springs, police interrogated her for three-and-a-half hours.

"I started to question myself and doubt myself, I guess that was a police tactic," she later told 60 Minutes.

"I think they were hoping I would confess to something I hadn't done.

"It was like a stab to the heart, how could they think that?"

Eventually, she was released without charge.

Then, in early 2003, police received a tip-off from a man who said he knew who did it. The name he gave was Bradley John Murdoch.

Police pounced on their first good lead, taking a DNA sample from Murdoch, a mechanic from Broome.

The DNA was a match for that taken from Joanne's t-shirt, the gear stick in the Kombi, and the makeshift handcuffs.

Knowing the police were on to him, Murdoch escaped to the bush.

Police knew they only had a very small window of time in which to catch him, and that window was narrowing all the time.

Colleen Gwynne, the lead investigator in the case later recalled: "If he disappeared, we wouldn't have found him — he was an expert in disguise and he was an expert in not being found. This man knows the bush like no other."

But luckily, they did catch up to him, and he was arrested in Adelaide before being extradited to Darwin.

Police searched his home and Toyota Landcruiser. They found various rolls of tape, cable ties, night vision goggles, as well as a hair-tie belonging to Joanne Lees wrapped around the holster of his gun.

When it was presented in evidence, Colleen Gwynne said he recoiled back and would not touch it.

That was when she knew they'd got him.

Bradley John Murdoch was convicted of murdering Peter Falconio and assaulting Joanne Lees and depriving her of her liberty. He was sentenced to life, with a minimum parole period of 28 years.

Murdoch, who still protests his innocence, will never be released unless he reveals the location of Peter Falconio's body.

Earlier this month, Murdoch, now 61, was reportedly diagnosed with cancer.

So far he has served 14 years behind bars for Peter Falconio's murder. It's terrifying to think how easily that could have been Joanne Lees.