Ariella (1980)

The lonely young woman Ariella feels among strangers in her upper-class family in her own house. Ariella is discovering her sexuality and her arrogant mother Helena, her father Rodrigo and her brothers Clécio and Alfonso do not give love or affection to her. When Ariella overhears a conversation of her brothers, she learns that he biological father was lured by Rodrigo that had stolen his fortune and raised her as a daughter. Now Ariella plots revenge against her family using her beautiful body to reach her goal.