Mad men, mamas’ boys & murder: Ed Gein & Hitchcock’s Psycho.
Hollywood pushes “based on a true story” films quite often, not just in the present day with the success of movies like The Blair Witch Project (1999) or Paranormal Activity (2007), which were manufactured true tales, or stories faked in their “reality” by the filmmakers before the films themselves were written, made, and released. The true “true story” film, one that was made with some sort of input from an existing historical tale or anecdote, has been around for some time, likely since 1899’s Major Wilson’s Last Stand, a short war film dramatizing the deaths of Major Allan Wilson and his men in final engagement of the Shanghai Patrol in Rhodesia in 1893.
Indeed, many films that advertise that they are “based upon actual events” are only loosely based upon them, sometimes to absurd extremes. A Nightmare on Elm Street (1984), for instance, was technically “based on actual events” only in so far as a rash of otherwise healthy people dying in their nightmares for no apparent reason — see the LA Times articles which inspired Craven in this Reddit subthread — inspired the creatives to elaborate the story of Freddy Kreuger.
