In August 1990, two hikers sent photos of a strange diamond-shaped aircraft to the press – but the story never appeared. Was it a prank, a hoax, an optical illusion or something else entirely?

On a misty evening in August 1990, two men hiking on the moors surrounding Calvine, a pretty hamlet in Perth and Kinross, claimed to have seen a giant diamond-shaped aircraft flying above them. It apparently had no clear means of propulsion and left no smoke plume; it was silent and static, as if frozen in time. Terrified, they hit the ground and scrambled for cover behind a tree. Then a Harrier fighter jet roared into view, circling the diamond as if sizing it up for a scuffle. One of the men snapped a series of photographs just before the bizarre craft shot away vertically and disappeared.

Craig Lindsay was a press officer at the RAF base in Pitreavie Castle in Dunfermline, 50 miles away, when the Daily Record got in touch a few days later. The hikers, who worked as chefs at Fisher’s Hotel in Pitlochry, had sent six photos of the diamond to the newspaper and told their story. The Record’s picture editor, Andy Allen, sent Lindsay the best of the bunch.