FX

Don't blame us if you can't fall asleep at night, OK?

"American Horror Story" is known for its odd humor and grotesque charm, and every once in a while, it even manages to surprise us, albeit with a blood-soaked threesome or demented murder clown, but it's surprising nonetheless. The show's ability to always keep its audience guessing is one of the many reasons fans of "AHS" feverishly try and piece it all together before the season's end.

But even loyal viewers might not know the whole story. How much do you really know about "American Horror Story?" The FX anthology series has always been inspired by real events, but do you know which ones were ripped from the headlines and which were from the twisted mind of Ryan Murphy? Here are 13 unsettling facts about "AHS" that might just keep you up all night: