What is it about seeing the words "based on a true story" flash across a movie screen that sends an extra shiver down your spine? Even knowing that any "true story" used in a scary movie has been exaggerated and embellished within an inch of its life doesn't take away from the terror we feel: Omg, this actually happened to somebody! This could actually happen to me! But you know what's really freaky? Sometimes one incredibly disturbing real-life person or event can spawn several different horror flicks. Yikes! How messed-up is that? And just wait till you find out which of your favorite frightening films are based on the same "true" story!
Everybody knows the terrible tale of cross-dressing, knife-wielding mama's boy Norman Bates - but not everybody knows the character was based on Ed Gein of Wisconsin, who was arrested in 1957 for committing two murders and "digging up the corpses of countless other women who reminded him of his dead mother," which he then skinned to make everything from lamp shades to socks to a full-body "woman suit" in hopes of becoming a woman. Gein ended up dying in a mental institution (gee, ya think?!).
2. The Texas Chainsaw Massacre (1974):
Who can forget Leatherface and his cannibal kin? DAMN that movie scared the crap out of me. Anyway, Ed Gein's skin-wearing ways inspired this one, too. (As well as Hannibal Lecter, yes, in case you were wondering.)
3. The Amityville Horror:
Based on a book by George and Kathy Lutz about their supposed real-life experience living in a house that was so freaking haunted they ran screaming after only 4 weeks. (Lots of people say the Lutzes made it all up. But considering there was a mass murder at the house before they moved in, who knows?)
4. The Serpent and the Rainbow:
(This one's for all you Walking Dead junkies.) Based on a book by a scientist (Canadian Wade Davis) about the practice of "zombification" in Haiti involving a toxic powder which could place victims into a "death-like" state, only to be revived/controlled by evil zombie-masters.
5. The Hills Have Eyes:
Based on the on the 15th century Scottish legend of Alexander "Sawney" Bean, the supposed leader of a 40-person clan that lived in caves and killed/ate over 1,000 people over 25 years. (Most historians think the story is a load of malarkey. Oh wait, that's Irish, not Scottish. Anyway.)
Source : http://www.cafemom.com