This French psychological horror thriller is a masterpiece of suspense and intrigue. The film tells the story of two women, Christina (Véra Clouzot) and Nicole (Simone Signoret), who conspire to murder Christina’s abusive and sadistic husband, Michel Delassalle (Paul Meurisse), the headmaster of a boys’ boarding school. The plot unfolds as the women’s plan appears to succeed, but strange and unsettling events begin to occur