In 2017, the New York Times ran a front-page story about a Pentagon program called the Advanced Aerospace Threat Identification Program, hinting that unidentified flying objects had indeed been spotted. The UFO community was surprisingly skeptical. But why? To better understand, Sarah Scoles ventured from dark, conspiracy-filled corners of the internet, to a former paranormal research center in Utah, to the Pentagon, and of course to Roswell. Along the way, she introduces the field investigators, the rational people, and the unhinged kooks of this sprawling community.