First Half: Author and screenwriter Lisa Morton joins Lisa Garr (email) to explore Halloween's mysterious history and folklore, from its ties to the ancient Celtic festival of Samhain to centuries-old beliefs about spirits and the supernatural. She’ll also investigate the history of demonic possession, and why this season has traditionally been viewed as a time when the spirit world draws closer.

Second Half: Researcher and author John Kachuba will share experiences from his investigations of more than 100 haunted locations across the U.S. and abroad. Known as the Ghost Professor, he goes beyond ghost hunting to examine a deeper mystery: What are ghosts, why do we encounter them, and why are they found in virtually every culture?

6-10pm PT: Art Bell - Somewhere in Time returns to 8/12/97 for a night of Open Lines, and reporting from Linda Moulton Howe on a Bigfoot sighting in the Everglades.