The Dark Knight (2008)
The first time the Joker describes his scars, he says that they were made with a knife and were intended to create a smile. When Elizabeth Short was killed, this is exactly what was done to her face. Until the Manson murders in 1969, the Short murder and mutilation represented the most hideous and deeply shocking crime in all of Los Angeles history. The concept in this film that the Joker had a smile carved into his face adds to the terrifying nature of the character.