Les diaboliques 1955
Devilish Souls is a movie about two women who come up with a perfect murder plan. Michel Delassalle, who is the head of a school owned by his wife, is a truly unbearable character. He is cruel to everyone around him, including his wife, and he is having a secret affair with one of the teachers at the school, treating his lover just as badly. When this secret affair is revealed, the two women, driven by their hatred for this man, come together to seek revenge. They plan and execute a flawless murder, but an unexplained mysterious event complicates things.