How about the Halloween haunted house that is soooo scary that nobody can ever complete their tour? So-called witnesses claim this house has five stories, or levels, that get scarier on each floor and that most visitors turn back or just disappear.
The story is a very interesting urban legend that shows itself in the Fall, around Halloween. It often changes locations, depending on the writer. It's been reported to be in Ohio, Texas and Michigan, but no one can ever tell you exactly where it is. The person who claims to have been there is always a friend of a friend, or a cousin's friend etc., which is typical of urban legends because it can't be verified. It also never mentions who actually sponsors or funds the haunted house.
The details have some twists and turns too, including the prizes for completing the tour. One version states a $25 admission fee with $5 returned to the visitor after each level is completed. Not an easy task considering that each floor is scarier than the previous. Another version includes a large cash prize for anyone who can tour all levels, which has never been done. Some simply claim that you get your entire admission fee back upon completion.
To add some scare tactics, the stories elaborate about those who have been in the house and were never seen again. Some people disappear between the fourth and fifth levels. One guy was found almost scared to death, white hair and all. Of course, he had to be institutionalized.
It's kind of like the "telephone" game. The story gets better after it makes the rounds and everyone has a chance to add their own scary element.