Classic slice of stylish 1970s Euro-sleaze from cult director Jesus 'Jess' Franco. Maria (Susan Hemingway) is sent to Serra D'Aires convent after being caught in flagrante delicto by her parents. However, her parents could not possibly have known of the abuse their daughter would suffer at the hands of the monks and nuns in charge, who are secretly Satanists. Maria is tortured and raped by everyone in the place - including the horned Devil himself. After being abandoned by everyone, Maria begins to lose hope. She writes a letter to God and throws it from the window, where it is found, and Maria is briefly rescued from her fate by a Knight - before falling into the hands of the Inquistion and being burned at the stake.