Jacobs knows that people think he's crazy. He is a bona fide historian at Temple University--and a leading UFO researcher. He has interviewed, mostly under hypnosis, hundreds of people who say they have been abducted by aliens, and he thinks he's figured out why they are here--and it's not Whitley Strieber's mystical, New Age vision of cosmic harmony. Rather, it is interspecies breeding, because the aliens cannot reproduce themselves. ``The aliens are conducting a widespread, systematic program of physiological exploitation of human beings,'' he states. Jacobs gives vivid, detailed descriptions of the alien/human hybrids and mating and fetal implantation procedues, based on the accounts given by his interviewees. You can classify this with Star Trek or engage in a willing suspension of disbelief, which might be allowed Jacobs on the assumption that he, a solid academic, and the many, many people he interviewed--with similar accounts uninformed by prior knowledge of other abductions--can't all be crazy.