The world's foremost academic expert on UFOs and alien abductions provides the first evidence-based explanation of a mystery that has perplexed scientists for decades. Based on more than 700 hypnotic-regression interviews with alien abductees and a Roper survey of 6,000 adults, The Threat reveals why the aliens are here and what they want, explains why their agenda has been kept secret, and exposes their frightening plans for earth and its inhabitants...