Ghost Adventures investigates a former old folks home & orphanage, with thousands of deaths reported. The guys uncover horrifying tales of the Odd Fellows secret society, which used human remains for their dark rituals.

For their 100th episode, Zak, Nick and Aaron visit St. Louis to investigate the notorious Exorcist House, the site of the most famous possession in paranormal history, which was later portrayed in a critically acclaimed book and movie. The guys dig even deeper to learn about the original exorcism that occurred on March 16, 1949.