Lovers Lane (2005)

Sarah is a small town California deputy sheriff working on a brutal murder case of a young couple who were murdered after having sex in their car on the so-called "Lovers Lane" drive in the nearby woods. Sarah believes the killings are linked to the murder of her sister a year earlier. But Sarah's pompous police captain believes she's taking the case too seriously and hands the investigation over to a visiting FBI Agent. But Sarah finds it hard to stay away and secretly gets close to the agent on the case as more murders begin to happen.