It is considered to be one of the first books to popularize the concept of UFOs and to suggest that the US government was covering up evidence of their existence.In the book, Keyhoe presents a variety of eyewitness accounts and other evidence suggesting that UFOs are real and that they may be extraterrestrial in origin. He also argues that the US government has been aware of the existence of UFOs for some time, but has been covering up this knowledge in order to avoid public panic."The Flying Saucers are Real" was highly influential in shaping popular perceptions of UFOs and helped to launch a wave of interest in the topic that continued throughout the 1950s and 1960s. The book was also controversial, with some critics dismissing it as sensationalist and lacking in evidence. However, it remains an important part of the history of UFOs and continues to be widely read and discussed today.