In a run-down, fifth-rate French private school, murderous passions seethe just below the polite surface. Fragile Christina (Véra Clouzot) and enigmatic Nicole (Simone Signoret) — the put-upon wife and abused mistress of sadistic headmaster Michel Delassalle (Paul Meurisse) — conspire together to murder the swine, then dump his corpse in the weeded-over swimming pool in the hope that his death will be seen as a drunken accident. The scheme seems to be going fine, but when the pool is drained the body is missing and the women start to lose their minds, especially when a stray pupil claims to have seen Michel lurking in a perhaps-spectral manner. Soon, the women are also seeing things, something extremely ghastly shows up in the bath-tub, and a set of shocks and twists turns cruelly upon the characters (and the viewer) in the last reel.
In 1955, mainstream British and American audiences occasionally flocked to sub-titled films, and made this an international hit under the export titles The Fiends and Diabolique. The horrific mystery has lost only a fraction of its power over the years, though literally dozens of films (see: Deathtrap, Hush... Hush, Sweet Charlotte, Games etc.) have borrowed part or all of its tricky storyline. This was one of the first movies to depend on an M. Night Shyamalan-style twist ending which forces you to reassess everything you thought you had been told earlier in the film — and perhaps to watch it over again to see if the script plays fair with its clues.
Following the outdoor suspense of The Wages Of Fear, Henri-Georges Clouzot directs with a gray, claustrophobic cruelty that briefly made him seem a serious rival to Alfred Hitchcock. After drawing on Pierre Boileau and Thomas Narcejac, authors of the book that Les Diaboliques is based on, for Vertigo, Hitchcock made Psycho explicitly to reclaim his ‘Master Of Suspense’ title, and took care to follow Clouzot by setting his most horrible scene in the bathroom and building up to a twist ending. It has several strong moments of physical horror (one trick with contact lenses is still creepy), but roots its nastiness in everyday cruelty — as when Michel forces his wife to eat a disgusting school dinner — and the down-at-heel, despair-haunted school setting.