The Silence of the Lambs
One of the most famous serial killer movies of all time, The Silence of the Lambs follows investigative FBI agent Jodie Foster as she tries to get some information out of Hannibal Lecter. Strangely, Lecter actually turns out to be a somewhat kind and empathetic serial killer cannibal, and he helps the FBI track down a murderer who steals the skin of young women.