The Poltergeist

One bit a woman, leaving puncture wounds all over her body. Another attacked the contents of a warehouse full of glasses and mugs. Yet another lifted furniture into the air, then sent objects flying in another house. These are some of the strange and sometimes terrifying cases collected by poltergeist investigator William Roll. A parapsychologist, Roll studies these "noisy ghosts" to understand what they are and why they do what they do.

WILLIAM G. ROLL, Ph.D., is an Oxford-educated parapsychologist on the faculty of the Psychology Department of State University of West Georgia in Carrollton, Georgia. Over the course of his extensive career he has written three books and more than two hundred scientific articles. He has appeared on numerous segments of "Unsolved Mysteries," as well as the Discovery Channel and other television documentaries. In 1996 Roll received the Outstanding Career Award from the Parapsychological Association and in 2002 he received the Tim Dinsdale Memorial Award from the Society for Scientific Exploration.