Perhaps apocryphal, Clouzot claimed that he beat Alfred Hitchcock in a bid to buy the rights to the book upon which Diabolique is based, She Was No More (Celle qui n'était plus) by mere hours.

Pierre Boileau and Thomas Narcejac, authors of the novel that served as the basis for the film, wrote another novel, From Among the Dead (D'Entre les Morts), which Alfred Hitchcock made into Vertigo (1958).

In a very sad event mirroring the story of the movie, Véra Clouzot indeed turned out to have a weak heart and, a mere five years after filming, died at the age of 46 from cardiac arrest.

Simone Signoret was married to Yves Montand, star of Henri-Georges Clouzot's previous film, Le Salaire de la peur (The Wages of Fear, 1953). They were married until her death in 1985.

Signoret's previous husband was also named "Yves," after French film director, Yves Allégret.

Probably apocryphal, but nonetheless amusing, Roger Ebert reported on this story of a letter received by Alfred Hitchcock after Psycho (1960): "A man wrote to Alfred Hitchcock: 'Sir, After seeing `Diabolique,' my daughter was afraid to take a bath. Now she has seen your `Psycho' and is afraid to take a shower. What should I do with her?' Hitchcock replied: 'Send her to the dry cleaners.'"

Memorable Quotes from DIABOLIQUE

Christina Delassalle (Vera Clouzot): "Don't you believe in Hell?"
Nicole Horner (Simone Signoret): "Not since I was seven."
Christina Delassalle: "I do."

M.Drain, professeur (Pierre Larquey): "I may be reactionary, but this is absolutely astounding - the legal wife consoling the mistress! No, no, and no!"

Nicole Horner: [handing Christina the phone] "Here, take it. It doesn't bite. It doesn't slap, either."

Michel Delassalle (Paul Meurisse): [to Christina, having trouble swallowing rotten fish] "Everyone is looking at you! Swallow!"
Nicole Horner: "It's disgusting!"
Michel Delassalle: "Sorry?"
Nicole Horner: [to Michel] "Some things are hard to swallow, and I'm not talking about the fish!"

Christina Delassalle: [to Nicole] "I'd like to die and not see him anymore."
Michel Delassalle: [overhearing it] "Die, darling! Die and do it quickly!"

Alfred Fichet, le commissaire (Charles Vanel): "To commit suicide in the Seine, one doesn't need to undress."

Alfred Fichet, le commissaire: "The keys in the pool, the husband in the morgue! You dream too much about water in this house!"

Plantiveau, le concierge (Jean Brochard): "Watch out, ma'am. That's the deep part where you are."
Christina Delassalle: "There is no danger. I can swim."
Plantiveau, le concierge: "That don't mean a thing. It's always the ones who know how that get drowned. The ones who can't, don't go near the pool."

Nicole Horner: "I won't have any regrets."

Alfred Fichet, le commissaire: "I'll find him."

Christina Delassalle: "So it's a coincidence?"
Nicole Horner: "A coincidence, yes."
Christina Delassalle: "And Fichet. Was his being at the morgue a coincidence? And the suit. And the hotel. And now the children! Is it a coincidence that it's getting closer and closer?"

Christina Delassalle: "Who's there? Who's there?"

Moinet, une jeune Moynet (Yves-Marie Maurin): "I saw her. I know I did."

Compiled by Greg Ferrara