It’s a UFO story that will make the heart of any obsessive skip a beat: two young men take an astonishing photograph and then vanish after alerting the media.

That is what happened in August 1990, when chefs who were out walking on the edge of the Cairngorms after a long day at work snapped a diamond-shaped object hovering in the sky, as what looked like a military jet flew in the background.

But then, after they sent their image to Scottish newspaper the Daily Record, the two men vanished without a trace and the photo did not emerge in public until 2022, when it was published by the Mail.

It was an image that the Ministry of Defence and National Archives tried to keep hidden – and many files on the incident are still closed.

Now, a former MoD official who worked on the department’s ‘UFO desk’ has given his view on what he believes happened to the chefs.

Nick Pope said he believes a ‘fairly robust’ conversation was held with the pair to keep them quiet, but added to The Guardian: ‘The idea that that these people were assassinated by the deep state – that’s just nonsense.’

His comments come after a former colleague of the chefs at Fisher’s Hotel, Pitlochry,  previously told the Mail that it was like the two men had ‘vanished off the face of the Earth’.

Richard Grieve added that the pair were left ‘visibly shaken’ after two mysterious figures dressed in black suits arrived during a shift a few days later and spoke to them.

He claimed they then vanished four weeks later.

On August 4, 1990, they had driven 13 miles from their place of work to Calvine, a spot on the edge of the Cairngorms.

They had not walked for long when they saw the object, which was around 100feet long.

Terrified, the pair hid in the bushes and then heard the sound of a jet aircraft flying north.

At the time, two squadrons of Tornado fighters were based at nearby RAF Leuchars.

The pair then saw a jet circle the object before continuing on its original path.

Before it and the mysterious craft disappeared, the chefs took six images. They then took the photos to the Daily Record, which passed the images on to the MoD.

It remains a mystery as to why the Daily Record never ran a story.

Some suspect that they were handed what is known as a D-Notice – an official request not to publish a story due to national security concerns.

The newspaper’s editor at the time, Endell Laird, was on the MoD’s D-Notice committee, along with 13 other members of the media.

Mr Pope, who worked on the MoD’s UFO desk for three years from 1991 – the year after the Calvine incident – previously confessed that the ministry ‘buried’ the story.

He told 2024 UFO documentary The Program that the Daily Record’s story would have ‘blown our standard line out of the water’.

He added: ‘Therefore, we wanted to bury this – and we did.

‘All the photographs and all the negatives were acquired by the Ministry of Defence and they were never seen again.’

It was thanks to the quick thinking of a press officer in the RAF that the image that emerged in 2022 was released at all.

Craig Lindsay was contacted by the Daily Record shortly after they were sent the images.

He forwarded the standout shot to the MoD, who asked the Record to send the others, along with all the negatives.

Mr Lindsay had been the first official to speak to one of the young chefs after they took their photos.

The MoD had told him to tell the chefs to leave the case with them.

Incredibly, Mr Lindsay broke protocol by stashing a copy of the main UFO image in his bookshelf before he sent it, the other images and the negatives to the MoD on their orders.

Decades later, he was tracked down by investigative journalist and lecturer Professor David Clarke.

When the pair spoke for the first time in 2019, Mr Lindsay said: ‘I’ve been waiting for someone to call me about this for 30 years.’

Mr Lindsay handed over the image – which he had re-discovered in a stash of papers – on condition that it be handed back to either of the chefs if either of them ever came forward.

Professor Clarke then published the image in the Mail in 2022.

However, one key piece of information he only revealed later was that, written on the back of the image were the words: ‘Copyright Kevin Russell c/o Daily Record Glasgow’.

Professor Clarke had exhausted all attempts to find the mystery man.

The Daily Record said no one by that name had ever worked there, and trawling through 140 people of that name proved fruitless.

But, wherever the chefs are, dead or alive, Professor Clarke does not believe that what they saw was an alien craft.

He wrote in the Mail: ‘Sadly, I do not think that mysterious aircraft arrived from another galaxy.

‘I believe it was man-made somewhere in a secret hangar — and whatever it was remains on the secret list and highly sensitive.

‘The witnesses had simply been in that “million to one” chance of being in that particular place at that particular time, and needed to be shut up.

‘Remember, this was 1990, the Cold War was still a year away from thawing.

‘The Gulf War started literally days earlier. The world was — as many would argue it still is today — divided along “them and us” battle lines.’

The sighting came two days after Iraqi forces invaded Kuwait, kicking off the first Gulf War.

The futuristic American F117A stealth fighter – which was deployed in the conflit – had been in development for years before that.

Some of the prototype designs, including one called the Hopeless Diamond, resembled the craft seen in Scotland.

The Pentagon even admitted to having flown aircraft that had a ‘”saucer” or triangle-shaped appearance and were capable of hovering aloft.’

Professor Clarke told The Guardian that the MoD could ‘easily clear up’ the mystery by releasing conclusions of analysis they carried out on the Calvine photographs in 1990 and 1992.

He said they are ‘feeding the conspiracy theories’ by refusing to comment.

The expert also called on the chefs to come forward.

A spokesman for the MOD said: ‘The MOD has no opinion on the existence of extra-terrestrial life and no longer investigates reports of sightings of Unidentified Aerial Phenomena or Unidentified Flying Objects.

‘This is because, in over 50 years no such reporting to the Department indicated the existence of any military threat to the UK, and it was deemed more valuable to prioritise MOD staff resources towards other Defence-related activities.’