Hasta el viento tiene miedo (1968 Mexico)

 Hasta el viento tiene miedo (1968 Mexico)

aka

Even the Wind Is Afraid

In "Hasta el viento tiene miedo", a group of boarding school girls suffer from the torments of a authoritarian and conniving headmistress called Bernarda, who seems to unload of all her anger on the girls. In contrast, Lucia, the vice-headmistress, tries to be as easy-going as possible to make up for Bernarda's unkind behavior, earning that way, the girls' friendliness One night, Claudia, a student from the boarding school, suffers from a nightmare, in which she hears a ghostly voice that calls her name from the heights of a tower that is situated in the school garden. When she goes in and walks up the stairs, she opens a red door and finds the body of a blonde girl hanging from the ceiling. Claudia's classmates become so fascinated with that dreadful nightmare that they all go together to the tower to reveal the mystery, even though Mrs. Bernarda had forbidden the girls to go up there. Before they can reveal any mysteries, the headmistress arrives and catches the girls who were trying to disobey her rules. As a consequence, all the girls are punished and forced to spend their winter vacations at the boarding school. Furious with their headmistress, all the girls complain about their vacations, without realizing that something even more awful is about to happen. There's a ghost seeking for revenge and one of them is going to be chosen as a messenger and living avenger. (IMDB Francisco Rotondi) V&D