When the skeletal remains of Hollywood screenwriter Gary Devore were found strapped into his Ford Explorer submerged beneath the California Aqueduct in 1998 it brought an end to one of America's most high profile missing person cases.

The fact that Devore was on his way to deliver a film script that promised to explain the 'real reason' why the US invaded Panama, has long given rise to a slew of conspiracies surrounding the nature of his 'accidental' death.

It didn't help that Devore's hands were missing from the crash scene, along with the script, and that investigators could offer no plausible explanation as to how a car could leave the highway and end up in the position it was found a year after he disappeared.

Now the Daily Mail can exclusively reveal that Devore was working with the CIA in Panama and even a White House source concedes his mysterious death bears all the hallmarks of a cover-up.

The findings, published in a new documentary The Writer With No Hands, are the first testimonies ever aired that give credence to the theories that surrounded the case in the late 90s.

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Mystery: Gary Devore was a revered writer before he mysteriously disappeared on June 28, 1997, on his way to deliver a controversial script about the US invasion of Panama alleging there was an ulterior motive

Accident? Devore, a former truck driver, was found dead in the California Aqueduct a year later but his Toshiba laptop contained the finished script was missing from his Ford Explorer, as were his hands

Chillingly, the British research team - which was warned to drop the investigation by a Department of Defense contractor - has also secured testimony from the coroner which reveals the human hands said to be recovered from Devore's car were in fact around 200 years old.

'Someone in authority lied. Or made a shocking error,' producer Dr Matthew Alford tells DailyMail.com.

'There could be an innocent explanation for the hands but it is as extraordinary as the conspiracy theory and very suspicious.'

Devore, who wrote Dogs Of War, Raw Deal and Time Cop, had been working on his directorial debut: The Big Steal.

Once a truck driver, he had made a successful career shift into Hollywood. He was a friend to Arnold Schwarzenegger, Tommy Lee Jones's best man, and ex-boyfriend of Janet Jackson.

The Big Steal, he told friends, would be 'the hardest hitting film studios have ever seen', featuring 'disturbing details' about the US invasion of Panama.

The first draft of the script, shown exclusively to the Daily Mail, tells the story of American operatives robbing a Panamanian bank to cover up for 'something much more serious'.

His widow, Wendy Devore (pictured with Devore) has since discovered he spent time in Panama with the CIA

Hollywood: Devore (left) became a screenwriter, working with actors and friends like Kurt Russell (right)

Revered: He wrote the script for Raw Deal, which starred his close friend Arnold Schwarzenegger in 1986

Discrepancies? These are the bones that were sent to a coroner for Devore's autopsy. The coroner told British producer Dr Matthew Alford he believes the bones to be around 200 years old

Revelations? General Manuel Noriega (pictured being detained by the US Marine Corps) allegedly had a stash of sex tapes featuring senior CIA officials which he recorded during parties thrown at his home in Panama

One line reads: 'With good natured suspicion, Romos speculates on US intent. All this to pick up Noriega?'

Another: 'It sounds like the Pentagon planned the bank robbery and the war is just a diversion.'

Devore's research for the end product included an article from London's now defunct Sunday Correspondent alleging dictator General Manuel Noriega had compiled a stash of sex tapes featuring top-ranking US officials.

Noriega, the article explains, ran a well-known 'honey trap': inviting diplomats to his home filled with alcohol, drugs, beautiful women, and beautiful men - and covertly filming their antics.

After years of research, Dr Alford suggests the film may have implied the invasion was nothing more than a diversion that would allow the US into Panama to steal back incriminating photos of senior US officials that Noriega could have used as blackmail.

According to Devore's widow Wendy, there was a constant stream of phone calls from CIA officials in the month leading up to Devore's death.

She told DailyMail.com: 'When we first married he told me he got a lot of calls from government agencies. He told me to ignore it, so I did. If the phone rang, I could take a message or say he was out, but not to speak to them really.

'We had a few at first, then not very many. Then in the last month one man was calling all the time.

'He was dealing in things that you're not necessarily supposed to deal in.

'I found out a lot of people in Hollywood had these connections with the CIA and knew things that will never be made public.

'After he disappeared, things just didn't add up.

'It's very easy to sound like a conspiracy theorist, but when you're married to someone you know little things about them that seem insignificant but are actually crucial. I know there are things that don't add up.'

The CIA declined to comment.

However, a former White House official from the Regan/George HW Bush era has now confirmed to documentary producer Dr Matthew Alford, that Devore harbored a deep-rooted relationship with the agency and traveled with officials to Central American companies including Panama. Documents also reveal the relationship was investigated by the FBI.

Speaking on camera, he concedes the case has the hallmarks of a cover-up.

Relationships: Devore dated Janet Jackson (left) and was briefly married to actress Claudia Christian (right)

Ex-wife: Nat King Cole's widow Maria Cole married Devore in 1969. They divorced in 1978

Other girlfriends: He also went out with actresses Season Hubley (left) and Patricia Barnes (right)

Devore's widow, who has since looked into the allegations, said she has discovered Gary traveled to Panama with a senior CIA official when he had said he was going to a location with his production team.

Wendy told DailyMail.com: 'I think the information that I have learned since he disappeared has pointed very strongly to the fact that he had another life and it points to the intelligence community certainly.

'I was never told about it beforehand because I think it was another method of keeping me safe and keeping me from asking questions.

'He told me he was going on location 'reckies'. I think sometimes he was but I have since found out he often wasn't with the crews he said he was.

'He went away a lot with members of the CIA special ops. They went to Panama together.'

On the night of his disappearance, Devore, aged 55, had gone to the Santa Fe home of his friend and long-time collaborator, actress Marsha Mason, on June 27, 1997, to finish the final draft of the script, carrying all his research on his Toshiba laptop.

He called Wendy late that night to say he had finished and was driving home with the finished piece.

At 1.15am, he said he was around four hours away and might stop at a motel to polish the script. Wendy told him to come home because he had a party planned for the next day to watch Mike Tyson's notorious fight against Evan Holyfield. That was the last contact anybody had with Devore.

Within a week of his disappearance, men from the FBI, CIA, NSA and DOD arrived at the couple's Santa Barbara home.

He went away a lot with members of the CIA special ops when I thought he was filming. They went to Panama together Devore's widow, Wendy

After an official went into his office, the computer was wiped of information. Devore's remaining research material disappeared during this period.

A search team spent a year tracking Devore's gas station stops and cell phone signal. They pinpointed his route on the Highway 14 south of the Mojave desert, and all the land around that route.

Finally, an amateur detective Douglas Crawford had a 'hunch' that he could be under the California Aqueduct, as that was the location of another recent death.

Although it had already been searched by helicopters and people on the ground, he was right: Devore was there.

When Devore's car was found, his Toshiba laptop was not in the car, nor was his gun or ammunition which had been under the seat.

Crawford refused DailyMail.com's request for a comment on this investigation.

A police report stated Devore had evidently driven off the aqueduct, which Dr Alford disputes.

'Newspapers speculated that Gary stopped for a break and then got back on the freeway travelling the wrong direction. However, to do this, Gary would have needed to have ignored 'Do Not Enter' signs and driven over two miles the wrong way on the freeway without realizing.

'Despite the crash happening at night and there being no lighting on the freeway, Gary's car headlights were found in the "OFF" position. I consequently tried driving like this and it's horrific and impossible.

'Gary had worked as a professional long haul driver, so friends and family do not believe he would have done anything daft on the road, even if he was tired.'

Wendy, whose request to read the confidential police files was refused, agrees.

'There are things that don't add up,' she said. 'When he called me the last time he sounded strange and agitated.

'When they found him in that aqueduct, which had been searched already by the way, he was wearing a seat belt with his wallet in his back pocket.

Crime scene: Police said Devore accidentally drove on the wrong side of the aqueduct and drove off the side into the water. British producer, Dr Matthew Alford, simulated the route and claims it is near-impossible

Search: Devore's widow says she had hired a team to search the area a year before he was discovered

Pulled out: The case was signed off and the CIA and Santa Barbara police state it was an accidental death

'Ask anyone who knew Gary: he never wore seat belts, and truck drivers never drive with their wallet in their back pocket.'

For 18 years Wendy has been calling to see the confidential reports done on her husband's disappearance, and broadcasting her belief that the CIA had a hand in it.

The agency is openly cooperative with Hollywood: in 1996, the role of Entertainment Liaison Officer was created to provide filmmakers with factual advice and authentic props.

Chase Brandon, a CIA operative who was a special operative in Panama for 25 years (and Tommy Lee Jones's cousin), was appointed.

The agency does not deny that, before Brandon's appointment, filmmakers gathered research on CIA language, style, systems, and even operations on an unofficial basis.

Indeed, Tricia Jenkins, author of The CIA In Hollywood, told DailyMail.com she has recently acquired new evidence showing how the CIA worked off-the-books to influence Hollywood scripts to an extent never previously known.

She said: 'In this documentation, concerning one major Hollywood movie, it is clear that the CIA functioned as the principle partner in shaping the original script and its influence exceeded that which would have been filled by an aggressive producer or studio executive.'

Devore's meetings however were 'beyond anything that could be considered normal for a screenwriter,' Alford says.

One of Hollywood's top private investigators Don Crutchfield, hired by Wendy Devore in 1997, attributes immense importance to the script.

'If I had that script in my hand, I could tell you what happened to Gary Devore,' said Crutchfield, who has worked for Michael Jackson and The Beatles after working as a bodyguard for Marlon Brando and Frank Sinatra.