In a small town in Mexico, Matea (Isela Vega) is an orphan who assists the priest, Father Feliciano (Mario Almada), in his parish. The village doctor tries to seduce her, but fails and proceeds to defame her into believing that Matea maintains relations with the priest. The people believe him and demand to cure her; he refuses and locks himself away with Matea. During the lockdown, they develop a passionate love, but fate arrives and the priest dies. Matea becomes a kind of priestess which is known as the "Black Widow".