In the 1860s, Giorgio (Giraudeau), a young Italian soldier, is sent to a remote post, far away from his lover, Clara (Antonelli). He is lodged in the house of the colonel (Girotti). He becames friends with the colonel and the local doctor (Trintignant). Among the inhabitants of the house there is a strange young woman: Fosca (d'Obici) who is both unattractive and mad. However, she has a passion that Giorgio will have to cope with.