THE STRANGE DOOR aka EMMURÉ VIVANT - 1951

Un château, un frère jaloux, une porte toujours fermée, un donjon, la vengeance au coeur d'un aristocrate: voilà les ingrédients d'un film d'horreur basé sur un récit du créateur du Dr Jekyll et Mr Hyde. Sire Alain de Maletroit plots revenge on his younger brother Edmond for stealing Alain's childhood sweetheart, who died giving birth to Edmond's daughter Blanche. Alain secretly imprisons Edmond in his dungeon for 20 years and convinces Blanche that her father is dead. Things get more complicated, as we can guess.