It is testament to the quality of a horror film when even the special effects test shots frighten the pants off you.
And newly emerged footage from the making of The Exorcist does just that.
The grainy practice shots from the 1973 film show Regan MacNeil, the movie's young protagonist, practicing levitating in her bedroom.
She is also seen violently thrashing about her bed, possessed by an evil entity.
Movie website Bloody Disgusting got its hands on the never-before-seen special effects footage this week, publishing it for its fans as a Halloween treat.
The Exorcist - directed by William Friedkin - tells the frightening tale of MacNeil, an innocent girl inhabited by an evil entity, and her mother's frantic resolve to save her with the help of two priests.
The movie was controversial from the day it opened and still shocks and haunts audiences today.
According to Bloody Disgusting, the author of the original novel, William Peter Blatty, can be seen in the practice footage, supervising the special effects.
Mr Blatty, who was the film's producer and screenwriter, is shown standing by as young actress Linda Blair floats into the air, slowly spins around and then sinks back down to her bed.
source: dailymail