Doctor X is a 1932 American pre-Code mystery horror film produced jointly by First National and Warner Bros. Based on the 1931 play originally titled The Terror by Howard W. Comstock and Allen C. Miller. Directed by Michael Curtiz and stars Lionel Atwill, Fay Wray and Lee Tracy.
Daily World newshawk Lee Taylor is investigating a series of pathological murders that have taken place over a series of months in New York City. The murders always take place at night, under the glow of a full moon, and each body has been cannibalized after the murder. Witnesses describe a horribly disfigured "monster" as the killer.
Doctor Xavier is called in for his medical opinion, but the police have an ulterior motive. They want to investigate Xavier's medical academy, as the scalpel used to cannibalize the bodies of the victims is exclusive to that institution. Aside from Xavier, the other suspects are: Wells, an amputee who has made a study of cannibalism; Haines, who displays a sexual perversion with voyeurism; Duke, a grouchy paralytic; and Rowitz, who is conducting studies of the psychological effects of the moon.
The police give Xavier 48 hours to apprehend the killer in his own way. During this time, reporter Taylor investigates the doctor's intentions and in the process, meets Joanne Xavier, the doctor's daughter. Joanne is exceedingly cold to Taylor, particularly after finding out that it was his story that pointed a finger at her father and ruined his first attempt at locating the killer. Taylor takes a romantic interest in Joanne, despite her hostility.
At Dr. Xavier's beach-side estate, all of the suspects gather for an unorthodox experiment. Each member is being investigated except Wells, because the killer has two hands and Wells has but one. Each man is connected to an electrical system that records his heart rate. When a re-enactment of the murder of the cleaning woman appears before them, the detector will expose the guilty man. Dr. Xavier's butler and maid, Otto and Mamie, carry out the reenactment.
During the experiment, a blackout occurs. When power is regained, it is discovered that Rowitz, whose monitor supposedly revealed him as the guilty party just before the blackout, has been murdered by use of a scalpel to the brain. Later that night, it is discovered that Rowitz's body has been cannibalized.
The following evening, Xavier asks Otto and Mamie to re-enact another of the murders. Mamie is too frightened to play her part, so Joanne takes her place. All of the men, save for Wells, are this time handcuffed to their seats, and the doors locked to keep Wells at the recording cabinet.
During the experiment, Wells sneaks into a secret laboratory where he transforms himself with "synthetic flesh" into the monstrous Moon Killer. After strangling Otto, Wells reveals to his horrified colleagues that he has been committing the murders to collect living samples of human flesh for his experiments. He declares his intention etc.....
