Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
The movie is based on a 1946 novel by Mary Jane Ward. There are no snakes in it, but both the book and movie helped to popularize the term "snake pit" to refer to overcrowded and squalid mental hospitals and inspired changes in state laws concerning mental health issues. The movie received six Academy Award nominations, including Best Picture, and Best Actress for Olivia de Havilland who portrayed an asylum patient named Virginia Stuart Cunningham.
This is the scene in which Virginia describes feeling as if she had been thrown into a snake pit:
Virginia Stuart Cunningham: "It was strange, here I was among all those people, and at the same time I felt as if I were looking at them from some place far away, the whole place seemed to me like a deep hole and the people down in it like strange animals, like... like snakes, and I've been thrown into it... yes... as though... as though I were in a snake pit..."
Doctor Mark Kik: "A snake pit?"
Virginia Stuart Cunningham: "Later, weeks later, I understood. I remembered once reading in a book that long ago they used to put insane people into pits full of snakes. I think they figured that something which might drive a normal person insane, might shock an insane person back into sanity. Did you ever hear of that?"
Doctor Mark Kik: "Yes."
Virginia Stuart Cunningham: "Well, it was just as though they'd thrown me into a snake pit. And I was shocked into thinking that maybe I wasn't as sick as the others... and I really might get well."