Absurdly Short Production Time: Stevenson wrote the first draft in under three days. After substantial criticism from his wife, Stevenson burned that draft and rewrote the story in under six days.
Adaptation Overdosed: There have been hundreds of film and play adaptations of the book, as well as references in popular media.
Based on a Dream: Allegedly, the idea for the story came from a fever dream. Many rumours tie the origins of the story to Robert Louis Stevenson's cocaine addiction.
Creator Breakdown: The popular story is that Robert Louis Stevenson wrote the novel after a particularly vivid nightmare. Even if this isn't true, then the novel's themes of duality and of a man suffering drastic personality shifts and driven to ruin by what is essentially an escalating drug addiction probably rang true with the author, who was not unfamiliar with such situations.
Life Imitates Art: Jekyll theorizes that every man may be more than just two men, each with their own role. Roughly thirty years later, Sigmund Freud publishes the ideas of the id, ego and superego.
The 1941 movie provides examples of:
Cast the Runner-Up: Ingrid Bergman was cast as Jekyll's virtuous girlfriend Bea, and Lana Turner was supposed to play Ivy, the slutty barmaid (and implied prostitute). Bergman, bored with playing righteous heroines, requested that the roles be reversed, and they were.
Underage Casting: Spencer Tracy was cast despite concerns that he was too old to play Jekyll at the age of 41. The irony being that in the original story, Jekyll was 50.
The studio's original choice for the lead role(s) was Robert Donat.
Despite having not yet met his famous co-star, Spencer Tracy wanted the characters of Ivy and Beatrix to be played by the same actress, Katharine Hepburn, to reinforce the theme of the good and bad qualities in every individual.
Vivien Leigh turned down the role of Ivy so she could film That Hamilton Woman.
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