1976 film by Leopoldo Torre Nilsson

1974 film by Daniel Tinayre

Nazareno Cruz is the seventh son of a couple living in a high mountain village. According to a myth, a seventh son will become a wolf on nights of the full moon. Everyone in the village is relieved when this doesn't happen. The boy grows up and falls in love with a beautiful girl, Griselda. When he's 20 years old, he is visited by the Devil, who offers him the wealth of the world if he will turn his back on his love for Griselda, and if he fails to do this, he will become a wolf.

The drama tells the story of an Argentine elementary-school teacher sent by the government to a rural hamlet located in the northwestern province of Jujuy. It shows how he touches the lives of the villagers, especially the young and impressionable boy Verónico, whose mother died and father left to seek work when he was an infant. The film is based on a non-fiction book written by Fortunato Ramos, a rural teacher in northwest Argentina, that discusses his teaching experiences.