By the summer of 1990 the phenomenon of crop circles was attracting large amounts of media attention. A group of researchers, who described themselves as 'cerealogists,' set out to solve the mystery of the circles' formation once and for all. They camped out on a hillside in Wiltshire with an array of heat, light and sound detectors, in the hope of recording the creation of a crop circle.

Operation Blackbird, as it was called, was led by ceralogist Colin Andrew. But its funding came principally from the BBC and Japan's Nippon TV. The British Army also provided assistance.

On the second night, July 25, the Operation appeared to meet with success. The monitoring equipment recorded flashing orange lights in the adjacent field. The next morning Andrews excitedly told the waiting media that two large circles with parallel lines running through them had formed during the night.

Unfortunately for Andrews, he spoke too soon. When the researchers examined the circle more closely, they found the calling card of a hoaxer awaiting them. Someone had suggestively left a board game (reported to be a Ouija Board) and a wooden crucifix in the middle of the swirled stalks. Andrews admitted that the flashing orange lights had probably been the heat signature of the hoaxers running around in the field. He told the press, "Somebody had a joke, but it has actually set our research back. We have a serious job to do. It is only funny for 60 seconds."

The identity of the hoaxer has never been determined, but the event seriously undermined the efforts of the cerealogists to be taken seriously. Conspiracy theorists suggested that the army itself had perpetrated the hoax in an effort to undermine the credibility of the researchers.