During the night, a Highway Patrol Officer knocks on the window of the car - but wrongly thinks they are parking. He soon turns aggressive and tries to get Emily Blunt into the back of his car. It only stops when Ashton Holmes smacks the Officer over the head with a bar and then he disappears, and the couple are back in their seats again.
Blunt then has nightmares and relives some of the backstory, with a little help from the newspaper they have plastered against the open window, to see that the Officer has been driving up and down the road in the past, killing whoever he meets. All the people they have seen are his victims and ghosts.
Ashton Holmes' character soon lets on that he is more injured than he made out. Blunt has an idea to use a phone headset that is conveniently in the car and climb a telephone mast with a box and try to contact help. Before she goes they kiss, and she tells him to warn her when the radio skips to a 50s tune, to indicate that the bad guy is on his way.
Blunt gets to the top of the mast, dials 911 and signals for help. She gets back to the car - but to find that her friend has passed away.
Soon a tow truck calls by. She hesitates but joins the driver. He tells her about the story of the area - basically that the Patrol Officer was evil.
Suddenly a car is racing towards them and drives them off the road. The other car crashes down a ravine, and the tow truck driver goes to investigate. Somehow we're now back in time, and the two of them look on as the Priests are first on the scene and the car wreckage is that of the Patrol Officer. The Priests decide not to help and the Officer is killed in the fire. As the tow truck driver looks on, the Officer's ghost crawls out of the wreck and freezes him alive.
Blunt realises that somehow she's back at her original spot and parked car. She gets back into the tow truck and tries to drives off. The Officer arrives to stop her, but Ashton's ghost appears and hits him again, and they're back in a cycle. She sees Ashton's ghost outside the car in the woods and follows him. They go past the Priests' house, and finally arrive at the service station where she can call for help.