[Source](http://reddit.com/r/AskReddit/comments/8htqnq/what_strange_thing_have_you_witnessedexperienced/dymn5c1) 
Worked in a haunted attraction for 5 years and one comes to mind.

I played a stereotypical Crazy doctor in a scene with other actors. The basic layout is you would enter the hospital, get on an elevator (fake), go down a toxic hallway, and finally meet me. The walls were thin and made of plywood. 

I remember one night - Group walks in already screaming. I think "Awesome, easy scare and easy group!" They step in the elevator and lose it. I hear them run out the elevator and toward the hall. I get ready in my normal position. I would stand behind the door to my office and scare people out of the scene - this didn't happen.

This group crashes through the wall. I scream like a little girl - which scares them more! They run through another wall! At this point, I just want them out to get my scene back in order. But then another actor from another scene shows up at the exit with a chainsaw. The groups run through their makeshift doors back through my scene. We had to then scare them back through the scene to get them to move on. 

People were banned from bringing chainsaws in my scene after that.