A fitting event for Halloween weekend in the nation's capital? The commemoration of Georgetown's "Exorcist Steps," made famous by the eerily frightening film "The Exorcist," which premiered in 1973.

The R-rated tale of an exorcism is based loosely on actual events. The bestselling novel by William Peter Blatty, a Georgetown University graduate, was inspired by a reported exorcism of a young boy that took place in Mount Rainier, Md., in 1949. Here is the story that appeared in The Post. The gist of the film: When young Regan (Linda Blair) starts acting odd -- levitating, speaking in tongues -- her worried mother (Ellen Burstyn) seeks medical help, only to hit a dead end. A local priest (Jason Miller), however, thinks the girl may be seized by the devil. The priest makes a request to perform an exorcism, and the church sends in an expert (Max von Sydow) to help with the difficult job. (Read more about "The Exorcist" in this Washington Post story.)

The ceremony Friday commemorating the famous steps too place at 4 p.m. The top of the steps are located on Prospect Street NW and lead down to M Street NW. Fans of the frightening film can join Academy Award-winning director William Friedkin, Academy Award-winning screenwriter William Peter Blatty, Mayor Muriel Bowser, Ward 2 Councilmember Jack Evans, and organizer Andrew Huff of the D.C. Office of Motion Picture & Television Development at Friday's ceremony.

Some say the steps are finally getting the recognition they deserve. "For Andrew Huff, lover of horror films, the 75 steps in Washington, D.C., where Father Karras plummets to his death in "The Exorcist" are his Lincoln Memorial," The New York Times reported. "I go to the steps all the time," he told the newspaper, "and when visitors come to Washington, I always take them there."