In the 1950s, there was a massive boom in noir thrillers hitting movie theaters, with Alfred Hitchcock taking the lead with his stone-cold classics Strangers on a Train, Dial M for Murder, and Rear Window.French filmmakers like Henri-Georges Clouzotwere keeping pace, and following his masterpiece, The Wages of Fear(remade by William Friedkin as Sorcerer decades later), Clouzot adapted the French novel, She Was No More, written by Pierre Boileau and Thomas Narcejac, into Les Diaboliques. Clouzot cast his wife, Véra Clouzot, as Christina, wife of the cruel principal of a French boys’ school. When she tries to make a clean break from that toxic relationship, she is convinced by her husband’s mistress (Simone Signoret) that maybe killing him would be a more effective and definitive way to end his abuse. The plan is going as fine as it can until the body of Christina’s husband literally vanishes, leading to one of the most tense non-Hitchcock psychological thrillers, possibly of all time.