There's always speculation from fans as to what the next season's 'theme' will be and while nothing has been confirmed for their upcoming season there is talk of the creators attempting to get the rights to a character the internet knows and loves: Slenderman.
As to his involvement in AHS, we have no clue. Fans have already begun to theorize that he will be the focus of the next season while others believe him being in the show may be a clue as to the theme of the season as a whole. Now, the info was given to the media by an 'anonymous source' and in a matter of days after this news yet another 'anonymous source' said that the rumors were not true. Not too helpful to tell you the truth. But I'd like to believe that ole Slendy will finally get some primetime attention, though my prediction for the season will differ from some, if not most, fan theories.
Think of how many scary urban legends there are; Bloody Mary, the Hook-Hand Man, the Vanishing Hitchhiker, and Bunny Man Bridge. See! And I could think of those in a matter of seconds! Now think of how much horror has taken place in the woods. Yeah, pretty much all of it.
What if the next season revolved around a creepy stretch of woods that has some gruesome or mysterious history involving those that live on its' edges? You don't even have to make Slenderman real, you could have him be a recurring figment of someones imagination. Or maybe it takes place in a rural town where urban legends are treated with more seriousness as they're so disconnected with the rest of the world. Once again, Slenderman doesn't have to be real but it would be super cool to have him become a problem in the town as children begin to disappear. Heck, for all I know Slenderman may only get cameo appearance in a season with a different theme altogether!