Diabolique (1955)

Diabolique
Thriller, Mystery
The cruel and abusive headmaster of a boarding school, Michel Delassalle, is murdered by an unlikely duo -- his meek wife and the mistress he brazenly flaunts. The women become increasingly unhinged by a series of odd occurrences after Delassalle's corpse mysteriously disappears.
Starring
Véra Clouzot, Simone Signoret, Paul Meurisse, Charles Vanel, Jean Brochard, Pierre Larquey, Michel Serrault, Yves-Marie Maurin, Georges Poujouly, Thérèse Dorny
Directed By
Henri-Georges Clouzot