"Theater Guild on the Air" broadcast a 60 minute radio adaptation of the movie on November 19, 1950 with Fredric March reprising his film role.
Edgar Norton had first played Poole onstage in 1898.
Miriam Hopkins originally turned down the role if Ivy Pearson, saying she wanted to play Muriel Carew instead. She soon changed her mind when the director informed her many actresses in Hollywood could be cast in her place.
Miriam Hopkins was not eligible for an Oscar nomination because most of her performance was cut from the film when it was released due to censorship.
John Barrymore, who had made a big comeback in the 1920 silent version, was offered the leading role in this film but turned it down.
Mr Hyde's appearance was based on the Neanderthal man.
The characters of Muriel Carew and her father do not appear in Robert Louis Stevenson's original story. They are based on similar characters created by playwright T.R. Sullivan for his 1887 stage adaptation of the story.
The first horror movie ever to win an Academy Award.
The heavy make up he wore as Hyde almost damaged Fredric March's face.
The nephew of Robert Louis Stevenson appears in a small uncredited role.
The only version where Jekyll's name is pronounced correctly as "Jee-kall".
The remarkable Jekyll-to-Hyde transition scenes in this film were accomplished by manipulating a series of variously colored filters in front of the camera lens. Fredric March's Hyde makeup was in various colors, and the way his appearance registered on the film depended on which color filter was being shot through. During the first transformation scene, the accompanying noises on the soundtrack included portions of Bach, a gong being played backwards, and, reportedly, a recording of director Rouben Mamoulian's own heart. Only in the late 1960's did Mamoulian reveal how they were done.
The sound of the pounding heart in the transformation scene was Rouben Mamoulian's own, recorded after he ran up and down the stairs for two minutes.
When discussing whom to cast as Jekyll/Hyde, studio head Adolph Zukor initially suggested Irving Pichel for the part. Director Rouben Mamoulian turned it down because he wanted an actor who could play both parts convincingly and felt Pichel could only play Hyde. 'Phillips Holmes (I)' was considered and rejected for the opposite reason: he would have been a good Jekyll but a poor Hyde. Mamoulian then suggested Fredric March. Zukor felt that this was a bad choice because, up till then, March had been featured in mostly lightweight roles. Mamoulian insisted that March was perfect for the part, and Zukor acquiesced. In addition to winning March the first of his two Oscars, Jekyll/Hyde was the part that finally led to Hollywood taking him seriously in more demanding roles.
When Dr. Jekyll comes to Muriel Carew's house for the final time, she is playing "Aufschwung" ("Soaring") from Fantasiestuecke, Op. 12, by Robert Schumann. This is a particularly apposite choice of music for the film, because Schumann had created two alter egos reflecting two different aspects of his personality, the impetuous and passionate "Florestan" and the introverted "Eusebius." Much of his music criticism was written using one or the other as a pseudonym, and the two frequently appear in his music in one guise or another.