Diary of a Madman is a 1963 horror film directed by Reginald Le Borg and starring Vincent Price, Nancy Kovack, and Chris Warfield. The screenplay, written by producer Robert Kent, is an adaptation of Guy de Maupassant's short story "Le Horla" ("The Horla"), written in 1887 Cast Vincent Price as Simon Cordier Nancy Kovack as Odette Mallotte DuClasse Chris Warfield as Paul DuClasse Elaine Devry as Jeanne D'Arville Ian Wolfe as Pierre, Cordier's Butler Stephen Roberts as Captain Robert Rennedon Lewis Martin as Fr. Raymonde Mary Adams as Louise, Cordier's Cook Joseph Ruskin as The Horla (voice) Simon Cordier (Vincent Price), a French magistrate and amateur sculptor who comes into contact with a malevolent entity. The invisible - yet corporeal - being, called a "horla" is capable of limited psychokinesis and complete mind control. Cordier first interacts with the horla when he meets a prisoner whom the horla drove to commit murder. The horla possesses the inmate and attempts to k! ill Cordier, who in self-defense accidentally kills the man. The magistrate inherits the prisoner's troubles as the horla turns its hauntings toward him. As the horla begins to destroy Cordier's life, he fears he is going mad and seeks help from a psychologist, who effectively suggests a hobby. Cordier chooses to pick up his old interest in art, meeting a model along the way. The horla insists the model is not the charming jewel that Cordier sees, but instead a conniving gold digger, and compels
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