This is a serious, objective appraisal of the ""Flying Saucer"" question. However, the ""phenomenon"" dealt with are not the UFO's (Unidentified Flying Objects) themselves but the reports written by the witnesses. Mr. Vallee is a professional analyst specializing in mathematics and astronomy and this study is not to prove but to define and analyze documented evidence according to scientific procedure. Starting with a sharp look at the records of history which includes poking the spokes of Ezekiel's Wheel, he goes up to the present with an analytical breakdown. Many of the reports are reproduced at length and relate such extraordinary incidents as the UFO that made off with a heifer; four UFO's disconcerting the employees of an air-filter plant; and the wild night in Kelly-Hopkinsville, Kentucky. The author is the first to denounce hoaxes, fraud and glory-seekers and in his notes on documentation and research, he is adamant about thorough investigation. This is most valuable as a manual of analytical processes in this unexplored area but the author writes clearly enough to intrigue the layman with his breakdowns categories and classifications. The ""phenomenon"" is a compelling curiosity in itself, particularly with the staggering amount of material presented here.