I didn't know this...
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Though many films have gone through difficult or taxing production periods, The Exorcist had a rather extensive list of tragedies and deaths related to the film's production. Disaster after disaster kept plaguing filming until finally a priest was called upon to exorcise the set.
Perhaps the most bizarre occurrence during The Exorcist's production was the electrical fire that burned down the set. Set ablaze by a pigeon that flew into the light box, the fire occurred during shoots for the infamous exorcism scene. The film was put on hold for six weeks while the set had to be rebuilt. According to director William Friedkin, this is the strangest occurrence that made him question if the film was genuinely cursed.
But the fire was far from the only tragedy to happen during the film's production. Jack MacGowran, who played Burke Dennings in the film, died unexpectedly after contracting influenza. Vasiliki Maliaros, the actress portraying Father Karras' mother, also died before the film's release. What's especially creepy is that both MacGowran's and Maliaros' characters die in The Exorcist.
As if the deaths of MacGowran and Maliaros weren't terrible enough, their deaths weren't the only ones associated with the film. Other actors lost family, including Blair, whose grandfather passed during the film's production. Altogether, nine people related to the production are said to have died during the making of the film.
Read More:
Why Linda Blair Was Never The Same After The Exorcist - Looper