Shall We Dance? (2004) Just about any film with Susan Sarandon is pretty frightening, but this one adds Richard Gere for a real chill-fest! Beverly Clark is suspicious that her husband's late work nights are a cover story for an affair, but the the horrifying reality is he's taking lessons in ballroom dancing! The hair-raising climax features a dance competition, which I will not spoil here except to say you shouldn't eat a full meal before watching it.Billy Jack (1971) A self-righteous vigilante flick, but with hippies! What makes the concept especially terrifying is that people actually thought this was a good movie. Even more chilling is the soundtrack featuring "One Tin Soldier (The Ballad of Billy Jack)" by Coven.
Watch this if you dare!

Pretty Woman (1990) Arguably the most terrifying movie ever made. The premise? Being a prostitute is a good way to meet lonely billionaires who will fall in love with you. Takes horror to a whole new level.
