This book examines ufology and belief in extra-terrestrials as a cultural phenomenon. The author examines how 19th-century occultism, particularly theosophy, has been revitalized under the guise of scientific speculation and captured the popular imagination. Unexplained or mysterious phenomenon such as UFOs, alien visitors, crop circles and the evidence for the astronaut gods theory are habitually interpreted by those who claim to have witnessed them in scientific terms, a fact that the author believes can be explained partly by tensions and anxieties within society caused by political, social and technological change.