Hilary Evans co-founded the Mary Evans Picture Library with his wife Mary in 1964, and is the author of a number of books and articles on ufology, ghosts and other anomalous phenomena.

As for the ten ‘best cases’, this is, of course, an impossible request. But the Hessdalen lights are outstanding because they have been so thoroughly investigated, and the same goes for the 1980 Piedmont, Missouri, observations by Harley Rutledge.

One of the most impressive clusters of sightings was that reported by Frank Salisbury in his 1974 report ‘The Utah UFO display’. The 1959 Boinai Father Gill sightings continue to intrigue, as does the Crop Circles enigma, though for different reasons. And I would still love to know what, if anything, happened to Betty and Barney Hill! But really, there’s hardly a case in the files that doesn’t have its own dimension of speculation and wonder!

Whatever verdict posterity passes on the flying saucer phenomenon, it will surely prove to be of the same lasting fascination as the Witch Mania or the rise of fascism, and equally revealing as to human nature and the limits of human gullibility.