Sarah is really working with the truck driver. The monster truck driver hit his brother Fred and Sarah has been taking body parts from people and giving them to Fred. Everything she did with Adam, was all part of the "preperation" of Adam's body so Fred could use it. Adam slits Sarah's throat and Fred gets split in two. The monster truck driver gets stabbed in both eyes and in the stomach. But then he chases Adam outside where his friend (who we thought was dead) runs the monster truck driver over. Adam then gets in the truck and runs the driver over till morning. As they leave the remains of the driver say, "You can't kill me! Wussies!"