Mount Rainier

In 1973,The Exorcist, was a box office smash. Set in D.C., the film chronicles a Roman Catholic priest's struggle to save a 12-year-old girl from demonic possession. But The Exorcist has another, even more unsettling connection to the Washington area. William Peter Blatty, who wrote both the screenplay and the bestselling 1971 novel from which it was derived, was inspired by an actual case in which a 14-year-old Prince George's County boy was purportedly was possessed by the devil.