The bodies of the two young jackeroos lay in the Great Sandy Desert.

They were found on a remote seismic grid road among the spinifex scattered on the red earth about 500km south-east of Halls Creek.

The vast 290-square-kilometre expanse of red sand in northeastern Western Australia where James Annetts and Simon Amos perished is one of the most inhospitable places on Earth.

Temperatures had been in the mid- to high-40s when the teenagers abruptly vanished, making the earth so hot it burnt through the rubber soles of shoes.

It was only slightly cooler five months later when two surveyors happened upon their stricken vehicle.

The two station hands were found a kilometre apart.

Seventeen-year-old Simon's stripped and skeletal remains had been torn apart by camels and wild dogs, a bullet hole through the forehead of his skull.

The body of James, 16, which still bore some flesh, hair and clothing, was 19km north of their abandoned Datsun.

James Annetts went looking for adventure but found himself in a dangerous, isolated job in the Outback

James Annetts with his dad Les. The Annetts didn't want their son to go to the Outback station to work, but were reassured by the station manager's wife that all would be fine

On the roof of the car, the two boys had arranged an 'SOS' using spanners.  

Near the car was an arrow, made from a star picket and charred branches, pointing in the direction where they took off on foot. 

James, who had left a heartbreaking message to his family scratched on a water bottle found next to him, was thought to have pressed on further north and finally dropped dead from dehydration. 

And yet, according to James' father, Les Annetts, there was an uncanny similarity in what was left of the two teenagers which suggested that, at some point before their deaths, they had been tied up.

'They were both missing the same bone from their arms,' Mr Annetts tells Daily Mail Australia.

'James from the right arm, Simon from the left arm, the same bone missing as if their arms had been tied together. 

'My wife and I believed they were running from something, they were being chased. We believed Bradshaw, the black tracker, who followed their tyre tracks and he could tell they were being chased.

'When they got through Balgo, there were the tracks of another ute which came through a back way into Balgo and it was chasing them.'

Surveyors found the Datsun ute with 'SOS' spelled out on the roof in spanners on a remote track five months after the two teenage boys vanished in the vast Great Sandy Desert

Balgo, in Western Australia's Tanami Desert, is just one of the locations Les and his late wife Sandra Annetts visited or became familiar with in their long-running quest to find the truth of what happened to their son almost 40 years ago. 

After all, from the moment James went missing, in December 1986, it was the Annetts who had to do much of the investigation amid a botched police probe and inadequate search.

Les believes James and Simon died while being pursued as a result of what had happened to them after they were hired to work in virtual slave-labour conditions in WA's eastern Kimberley district.

From their suburban homes, James in Griffith in the New South Wales Riverina, and Simon in Adelaide, the boys had answered job advertisements calling for 16 to 18-year-olds to work on cattle stations.

Scratched on his water bottle was a heartbreaking message to his family which read: 'James, My Follt. I always love you Mum and Dad, Jason, Michelle, Joanne' 

A jackeroo in the quarters at the station, which were described as filthy, with sewage coming up through the showers and electric shocks when lights were switched on

The remote Outback where James Annetts perished is in northeastern Western Australia in a vast 290 square kilometre expanse of red desert

The ads stated 'no experience necessary'. For each of the teenagers, who didn't know each other before arriving at Flora Valley Station, it was meant to be their first big adventure.

Les and Sandra Annetts had been reluctant to let James go, concerned about his safety, meals, working conditions and wages.

But he was insistent that he wanted to earn his own money and, as Les says, James was 'a very quiet giant, but don't get him riled or he'll give you backchat'. And the station manager's wife, Vicki Loder, assured them all would be fine.

What the Annetts didn't know was the cattle industry was in depression and living conditions were sub-standard at Flora Valley and two associated properties, Nicholson and Sturt Creek stations.

Darwin cattle baron Peter Sherwin's Australian Stations Pty Ltd had bought the stations on which staff were kept at a minimum to cut costs.

James arrived in July 1986 at Flora Valley, which stretches from the Kimberley to the Great Sandy Desert, with Simon turning up the following month.

Flora Valley's manager, Giles Loder, was a man with a fierce reputation. Within seven weeks of their arrival, he ordered James to Nicholson and Simon to Sturt Creek to manage the stations alone.

The boys found themselves working seven days a week for a $100 wage. 

After James Annetts' (left) and Simon Amos' (right) remains were found in the Great Sandy Desert, a forensic investigation would find that James was missing his right humerus and Simon his left humerus, suggesting they were tied up, according to James' father

They did daily 'bore runs' to get water for the cattle, and checks that windmills and other equipment were working properly, meaning round trips of 12 to 14 hours a day over ungraded tracks in vehicles with no air conditioning.

The conditions were so substandard that a woman employed as a cook at Flora Valley until she quit in disgust over a pay dispute, Debbie Davis, would recall that 'when the toilets were flushed, sewage would come up through the floor. We would get electric shocks when we switched on a light.'

A former yard builder at Flora Valley said the owner and manager were authoritarian and unforgiving. 

Loder kept in contact with the boys via twice daily two-way radio calls to his wife Vicki at Flora Valley, but they had no other support.

Les Annetts said his son's entire four months of wages, aside from 'one tick of $35' was unspent when he disappeared. 'He hadn't cleared anything.'

On the night of Sunday, December 1, 1986, the boys, whose properties were 150km apart, took off into the desert in a white Datsun utility that was so unroadworthy it would only travel for a couple of hours at a time before it needed fixing.

To those who claimed the boys were running away, Mr Annetts points out that they both left behind wallets, cash and belongings.

Police would find $384 and an uncashed pay cheque in James’ room, along with letters from friends and relatives.

Black tracker Jungarri Bradshaw would later tell the Annetts that the boys drove in an easterly direction towards Caranya station, site of the Wolfe Creek Crater, the world's second-largest meteorite crater which features in the 2005 horror movie Wolf Creek

Black tracker Jungarri Bradshaw would later tell the Annetts that the boys drove in an easterly direction towards Caranya station, site of the Wolfe Creek Crater, the world's second-largest meteorite crater which features in the 2005 horror movie Wolf Creek.

They then went back because they couldn't get through the locked gate, and then crossed at Billiluna, an Aboriginal community, and turned south.

'He tracked them to Balgo, through Balgo and on to Yagga Yagga [an Aboriginal community]. They were being chased,' Mr Annetts says.

'At Balgo, another ute came through via a back road and chased them. They probably became partially bogged on a sand dune.'

Back at Flora Valley Station, standard protocol was if the boys missed two radio calls, a search patrol was sent out to their stations.

But Vicki Loder had left in November to give birth to her second child, and the replacement head stockman Shane Kendall, who was meant to conduct the radio calls, didn't send out a patrol.

While 48 hours passed from Monday evening to Wednesday evening, with no calls from James or Simon, no search patrol was dispatched.

Les Annetts, a glazier, pointed out to hostile police that the blood pattern on his son's hand was an arterial spray. Tests would prove it wasn't his son's or Simon's blood type

Flora Valley Station (above) in the Kimberleys was managed by the authoritarian Giles Loder who the young jackeroos hired by the owner found unyielding 

Giles Loder landed his plane at Flora Valley on December 3 and drove to Nicholson station, where he noticed James' belongings were still there, but not the jackaroo, and busied himself getting water to the Brahman cattle.

He drove to Sturt Creek station the next day and found that Simon was also missing, although his cigarettes and personal effects were there.

It was only then that Loder called police and reported Simon missing, but did not mention James Annetts.

The boys had now been missing for three days in heat of more than 40°C. It was unknown how much water they were carrying.

Les Annetts said the veteran researcher of his son's case, Norm Barber, who has written the book Death in the Sand, had accurately portrayed the twists and turns of what happened from the moment that James and Simon vanished.

Loder told police who had arrived from Halls Creek to search that there was a second boy missing, James, and that he believed the boys had stolen a vehicle and gone hunting, and may have met with trouble.

At this point, 96 hours had passed since the teenagers had last been in contact. Loder flew the police to search for the boys, landing at Caranya station.

A white couple who lived in the Tanami desert got a rough description from a group of Aboriginals of two white boys travelling in a ute near Balgo.

The three-year-old ute was so unroadworthy that it stalled often and was difficult to restart. It was an unlikely vehicle to take on a long trip through the desert

But instead of travelling south to Balgo, Loder's plane went north. He told police he had organised a ground search around Flora Valley, but this proved to be untrue, as he had simply told other young jackaroos to 'keep an eye out' for the missing teens.

At 2.45pm on Saturday, December 6, an officer from the NSW Police at Griffith phoned the Annetts to say WA Police had informed him their son was lost after going hunting, and that grave fears were held for his safety.

WA Police characterised James and Simon as thieves, and the sergeant at Halls Creek relied on Loder's knowledge of the area to spearhead the search.

After two days of inadequate and fruitless searches, police eventually hired tracker Jungarri Bradshaw who flew with a policeman to Balgo, where the Aboriginal community was not used to police and wary of authority in general.

The policeman, Drummond, was Aboriginal, but lighter-skinned and from a coastal community, and foreign to the Balgo locals. 

No one mentioned the two white boys who stopped at the Balgo store in an 'orange ute', which could have been James' white Datsun covered in red dust. Nor did they say the boys looked as if they were fleeing someone.

The Balgo elders did speak with Bradshaw, and he would later relate some of what he heard to the Annetts before he was 'shut up' by the police.

Back at Sturt Creek, Giles Loder and the Halls Creek sergeant flew over the station in ever-expanding circles, finding no clues.

The newspaper ad that both Simon and James saw that lured them to Flora Valley Station where they would live in harsh conditions until they left and then died in the desert

Another plane and a helicopter joined to search, but it was not enough to use a dozen men flying over 100,000 square kilometres of desert and bush. 

Police opined the boys had got lost while hunting, but Jungarri Bradshaw disagreed.

He later followed Datsun tyre tracks to the Tanami Road, but police didn't trust Bradshaw's tracking ability, distrusted Aboriginal people in general, and had no understanding of their knowledge of the land.

The Balgo elders had told Bradshaw that the boys had been killed, and their bodies would be found in the desert.

The media had descended on Halls Creek for what had become an international story about two boys missing in the Outback. One reporter wrote that police suspected the boys had stolen the station vehicle and driven home for Christmas.

The insinuation was that police did not believe the boys worthy of a real search.

The WA Police froze out James Annetts' desperate family. A pilot in NSW offered Les and Sandra his twin-engine plane with night search capability to fly to Western Australia to help look for the boys, if they paid for the fuel. Griffith locals raised $4,000.

The Annetts were informed that Giles Loder 'is not allowing any private planes to land at Flora Valley. The area is so remote and large that any person not familiar with the country would also become lost', but that a plane could land at Halls Creek's public airport.

Roads in the Kimberley region of far north Western Australia (pictured) are so poor it can take seven hours to drive 150km. James Annetts, 16, and Simon Amos, 17, were left alone on cattle stations about 180km apart and had to drive up to 14 hours a day checking water bores

When Sandra Annetts phoned one police superintendent in charge of the search, he told her the skies over the area were already too crowded for another plane.

By December 16, looking for the boys had become a backburner task for Halls Creek police.

But a single-engine plane dispatched by Perth police arrived there on December 18, just as daytime temperatures were reaching 45 degrees.

Over the next five days, the crew flew for 34 hours over an area of 18,334 square kilometres, none of which was south of Balgo. They flew back to Perth on December 22.

In mid-January, after borrowing money for a bus trip via Alice Springs and Katherine, Les and Sandra Annetts arrived in Halls Creek. A kind couple, Stan and Clare Tremlett, offered to put them up. 

Mrs Annetts had doubts the boys had 'gone hunting' or stolen the Datsun and felt James wouldn't have abandoned his job at the station without contacting them first.

James had written to his parents each month he'd been away. He wrote that he would fly back home for Christmas, returning between December 17 and 21, and then return to Nicholson Station.

In another letter, which was found sealed but unposted among his belongings, he stated that when he came home he would not be returning to Nicholson, and told his parents not to send any more mail there.

On April 26, 1987, surveyors marking out seismic lines for oil drilling prospects spotted the ute on the slope of a sand dune 

The Annetts had done their own research and learnt of the sightings at Balgo and the Tanami track.

Mrs Annetts told one journalist police had told lies. 'We learnt that instead of a continual air search, they sent up two planes and a helicopter for a total of one-and-a-half days.

'There was no further search until December 17, when planes were in the air for a total of about 36 hours. 

'They only flew as far south as Balgo, even though Les had told them to check the Canning stock route and Rabbit Flat.'

Les Annetts described the situation at Halls Creek as 'total confusion... no one knew what was happening. No one would believe us when we told them James would not run away without contacting us.' 

When they checked the boys' belongings at Halls Creek police station, they found  two rolls of undeveloped film which hadn't been developed and printed by police.

James' hat with the initials 'JAA' written inside was splashed with dried blood. Les, a glazier, knew how a cut artery sprayed blood and said that was the pattern of blood on his son's hat.

Halls Creek police were furious and scoffed at the Annetts' 'interference' in the case and their engagement with the media.

James' hat with the initials 'JAA' written inside was was splashed with dried blood. Les, a glazier, knew how a cut artery sprayed blood and said that was the pattern of blood on his son's hat

It would later emerge that the blood on James' hat was neither his nor Simon's but it was human, of unknown origin.

On January 27, 1987, seven weeks after the disappearances, the Annetts flew to Flora Valley Station where most of the jackeroos who had worked with Simon and James had shot through.

By this time the boys were certainly dead. Giles Loder offered no condolences, instead questioning why the boys had stolen his vehicle.

Vicki Loder handed over cheques amounting to almost $1,000 - James unpaid wages.

Back in town, the Annetts heard stories from Aboriginals and whites who had worked under the hard regime which operated at the Australian Stations properties and quit. 

They returned home in early February. They had three other children to care for, Jason, Michelle and Joanne, but lost interest in eating and both lost weight.

When the media whirlwind began to die down, Sandra Annetts announced that after spending their life savings to travel to Halls Creek, she was selling her wedding rings and furniture to fund another search.

WA Detective Inspector Arnold Ian Davies would mount the new search.

He concluded that the five-day delay in searching by police after Loder found the boys absent, and the implied blame that they were thieves, had made it nearly impossible to find them alive.

'A sad loss not forgotten by the people of the Kimberleys': The deaths of James Annetts and Simon Amos remain a mystery almost four decades after they disappeared in the desert

The reported sightings of the boys near Balgo by Aboriginals and others, totally ignored by searchers, would come back to bite WA Police. 

Les Annetts returned to Halls Creek with an Adelaide TV crew for the second search, on April 5, 1987.

Police were still hostile to the Annetts, and told the media the couple was telling them 'bulls**t' about the case. They visited Flora Valley, but were ordered off the property and then the jackeroos' quarters whose dirty rooms Les described as 'unfit for a dog'.

On April 26, 1987, surveyors marking out seismic lines for oil drilling prospects arrived at a spot in the Great Sandy Desert near White Hills, 200km south of Balgo.

It was a Sunday at 7.15am and halfway up a dune they spotted a Datsun ute, number plate HC 529. 

The men had heard the missing boys had been lost in this area. The 'SOS' in spanners on the roof was still intact after 20 weeks of wind and weather. So was the arrow on the ground pointing north.

Police arrived at the scene from Halls Creek and, joined by Aboriginal guides, drove in the direction of the arrow until they found Simon and James' camp. There was a strewn out line of white bones, Simon's, spread over a 50m radius, and scarred from teeth marks and surrounded by dog and camel tracks.

The hole in Simon’s forehead was smaller than the exit wound in the top of his skull.

Residents of an Aboriginal settlement the boys drove through said they saw another vehicle following the Datsun they were driving. Pictured is a diesel fuel station in the Kimberley 

The police continued on, and one kilometre north they saw a water bottle in the sand and stopped. A few feet away in the spinifex was what appeared to be a pair of Levi's jeans and a Dunlop volleys shoe.

Bones stuck out from the hips of the jeans, and one leg appeared to be intact, with its foot in the shoe. Further up a track was a flannelette shirt and a singlet, and then a backbone and ribs.

Then there was a head with the jaw still attached. 

On the lid of the water bottle, James Annetts had scrawled, 'James, My Follt. I always love you Mum and Dad, Jason, Michelle, Joanne'. On the handle were the words: 'I found peece'. 

James' utility knife was in one of the jeans' pockets.

The difference in the condition of Simon's and James' remains led the men in attendance to conclude that Simon had died long before James and had been killed before going into the desert.

Skinned animals in a paddock took up to two years to be reduced to bleached bones.

Officers at Halls Creek police station failed to conduct a proper search for the missing boys and believed the teenagers were car thieves and were hostile to the families

Les Annetts was still on his trip with the Adelaide TV crew when news came through. The media arrived at the crime scene in helicopters.

The boys' remains were examined at the Perth morgue. On Body 1, Simon's left humerus, the arm's long top bone, and his left ulna, the forearm's longer bone, were missing. 

When Body 2, James, was examined, his right humerus and left ulna were missing. Dental charts confirmed both teens' identities.

Les Annetts faced the media. Halls Creek police were still labelling his son and Simon Amos as runaway thieves.

It emerged that the message James had scratched on his water bottle for his family had been darkened by police with a pen for the cameras.

Les returned home. The Annetts buried James' remains at Griffith Lawn Cemetery.

In Halls Creek, two churches and the United Aboriginal Mission raised money for a plaque to commemorate the boys, and in May 1987, the Annetts and their three remaining children attended a memorial and unveiling ceremony.

A requiem mass was held in Adelaide for Simon.

An inquest by Western Australian Coroner David McCann opened in December 1987. It was meant to last two days, but would continue for years. 

Apart from determining the causes of death, it would investigate conditions for young workers on Outback stations.

Les and Sandra Annetts with their children Jason, Michelle and Joanne in 2015

Questions, even after the inquest's conclusion, continued to have no satisfactory answers. They included:

• Why were two teenagers from the suburbs sent out alone to huge and isolated cattle stations in a dangerous location with unreliable communications?
• Why did the police search for the boys not begin until four or more days after their disappearance?
• Why did police assume the boys had run away when they had left behind all their belongings, including their money?
• If the boys decided to run away, why did they use a vehicle which was unreliable?
• Why did police know nothing about blood on James Annetts' hat, which was recovered immediately after his disappearance? Was this connected with a bloody wound observed on one of the station employees?

The coroner found James died of dehydration and Simon from one rifle shot that went through his skull. 

But Les and Sandra Annetts remained deeply suspicious of their son's death and angry at what they believe was the incompetence of the police search for the boys, and lack of duty of care.

The Annetts would later sue Australian Stations over the psychiatric injuries they suffered during the months they waited for news of their son's fate.

They claimed their son died due to negligence of the company, which put him on an isolated outstation with a defective vehicle and no training in survival skills.

They further claimed the company failed to keep in radio communication with James and did not tell police of his disappearance for several days.

The WA Supreme Court rejected the couple's negligence claim in the year 2000, finding the they were too far removed from events surrounding their son's death to be compensated.

The High Court subsequently found Australian Stations did owe a duty of care to James's parents, which allowed them to plan an appeal before the WA Court of Criminal Appeal.

The family has never been satisfied with any explanation of why the boys had driven off into the desert.

Sandra Annetts died in 2016. She believed to the end that James and Simon had met with foul play.