The old-timey phrase Liar's Moon, pretty much means to be born under a bad sign or a falsehood of some kind, which in the deep south of East Texas could mean anything in this small town. Right after World War 2, very poor and working class teenager, Jack Duncan (Matt Dillon), is pretty sure he's just going to end up losing fingers on the pump jacks of the oil fields after his summer of fun is over. Then he meets Ginny Peterson (Cindy Fisher) and she is like no other girl he's ever met before. She's wealthy, sophisticated, and after boarding school is going to be heading off to Vassar in the fall. The two kids from opposite sides of the tracks though start having a summer fling after they meet near a swimming hole and immediately fall hard for one another. Ginny's dad doesn't approve of her dating the poor kid with no future and wants her to drop the relationship immediately, but they decide to hop over the state line to Louisiana where it is legal for 17 year olds to get married without their parents permission and tie the knot so her father will HAVE to give his blessing, right? Wrong, because her wealthy old man hired a private eye to turn up dirt on the Duncan family and soon discovers that he doesn't just know his mom, they are ex-lovers and were around the time Jack was born! So the Liar's Moon might end up meaning that Jack and Ginny are in-fact long lost half-siblings! Well the young couple keeps things pretty PG in this one, Ginny's friend Karen (Tonja Walker) is no stranger to sexing things up for fun in the small town and even gives a couple peeping toms a fully nude show through her bedroom window for the lone nude scene in this jilted lovers tale from 1981!