Quella Strana Voglia d'Amare is a 1977 Italian erotic drama directed by Mario Imperoli in which Angela and Marco, orphaned siblings living alone in a sprawling countryside house cut off from the rest of the world, are already deeply entangled in an incestuous relationship when a local priest sends a beautiful teacher named Claudia to educate them — but instead of breaking their bond, Claudia ends up sleeping with Marco, sending a jealous and possessive Angela into a violent rage, using the mute handyman Rocco to exact brutal revenge on her rival in a finale that crosses from erotic drama into pure giallo thriller.