In Movie Night, Louise, your girlfriend, and Holly, her younger sister, have invited you over to watch a film. While the movie is going on, Louise comes up with a seductive plan of her own. What would happen if Holly noticed you and Louise having a good time right next to her? Would she get so offended that she leaves, or maybe she would join the two of you in an exciting threesome? Of course, every guy dreams of having a three-way with his girlfriend's sister, and that's what might happen if everything works out.