From
The Paris Review Online, Billy Wilder interviewed by James Linville:
http://www.theparisreview.org/interviews/1432/the-art-of-screenwriting-no-1-billy-wilderPictures are something like plays. They share an architecture and a spirit. A good picture writer is a kind of poet, but a poet who plans his structure like a craftsman and is able to tell what’s wrong with the third act. What a veteran screenwriter produces might not be good, but it would be technically correct; if he has a problem in the third act he certainly knows to look for the seed of the problem in the first act.
