CBS

Season 4: Episode 23 - Roadkill

Roadkill: The BAU is called to Hartford, Connecticut to help stop a killer who is running over women with his car. In the beginning they believe this UnSub is using his car to simulate a rape; an impotent male overcompensating by using his phallic vehicle to destroy women. But as the victims change to include men we discover that this killer is actually taking revenge on people who drive similar looking cars, specifically, a red sports coupe.  The reason for this relates to an 11 mile strip of U.S. Route 6 dubbed "Suicide 6" by the locals because of the unusually high number of fatal car crashes that occur each year. (FYI: This is a real stretch of road and it's nickname already exists -- it doesn't come from the Unsub's actions.) The team eventually discovers the UnSub was himself in an accident on Route 6, a crash that killed his wife and left him a paraplegic. This is why he needs to kill with his car, he can't walk. Using hand controls to drive he stalks Route 6 looking for the red car that ran him off the road years ago. To stop him the BAU must uncover the truth about who is really to blame for accident that killed his wife.