"I once made a movie, rather tongue-in-cheek, called Psycho. A lot of people looked at this thing and said what a dreadful thing to do, how awful, and so forth.The content as such was, I felt, rather amusing and it was a big joke. I was horrified to find that some people took it seriously.
It was intended to cause people to scream and yell and so forth, but no more than screaming and yelling on a switchback railway.I’m possibly in some respects the man who says in constructing it, ‘how steep can we make the first dip?’ If you make the dip too deep, the screams will continue as the car goes over the edge and destroys everyone. Therefore you mustn’t go too far because you do want them to get off the switchback railway, giggling with pleasure.”
—Alfred Hitchcock, Hitchcock in His Own Words