Wind River

It is winter on the Wind River Indian Reservation in Wyoming when U.S. Fish and Wildlife Service agent Cory Lambert discovers the frozen body of 18-year-old Natalie Hanson, without shoes or proper winter attire, and with a blood-stained groin. Rookie FBI special agent Jane Banner arrives to determine whether a murder has been committed. The next day, Jane learns from Natalie's father that his daughter was dating a new boyfriend, but he doesn't know the man's name or whereabouts. The autopsy returns findings of blunt trauma and sexual violence, and confirms Cory's deduction that the girl had died from exposure, specifically pulmonary hemorrhage caused by rapid inhalation of sub-zero air. However, the medical examiner is unable to report that the victim was murdered, therefore preventing Jane from calling in an additional FBI investigative unit. Read more on Wikipedia.