- Enforced Method Acting: For the scene where the staff and students are served spoiled fish, Clouzot reportedly forced the actors to consume the genuine article.
- Real-Life Relative: Christina was played by Clouzot's wife Véra.
- What Could Have Been: The original film was adapted from the novel Celle qui n'était plus, by Pierre Boileau and Thomas Narcejac. Clouzot beat out none other than Alfred Hitchcock for the movie rights.
- Interestingly enough, Hitchcock would obtain the rights to another Boileau/Narcejac novel, D'entre les morts, a couple years later and make it into his film Vertigo.