What was that behind you? It was not a ghost if you are reading A Turn of the Screw, written by Henry James in 1898. It was not a ghost if you are watching The Innocents, the film adaptation directed by Jack Clayton in 1961. It was not a ghost, even if you are a bored governess with an unhealthy fascination with your kiddies. Uh oh, there it is again. What is that?--not a ghost. Knock, knock. Who is there? Still not a ghost--so what was it? It was overactive imagination, obsession, and just general craziness.
In the novella, the first time the governess finds a "ghost" she had been fantasizing about meeting a strange man. That sounds a little fishy to me. Then, she does not even describe Quint to Mrs. Grose. All she does is agree with the way Mrs. Grose describes him. None of her other "sightings" are verified by any other character either. The same thing happens in the movie. Maybe it is just bad acting, but there is never any indication that any other character has seen any spooks. Even if the children, Miles and Flora (Martin Stephens and Pamela Franklin), are glad to see the ghosts wandering around, one would think they would at least look surprised.
In the book and the film, our governess, named Miss Giddens in the movie and played by Deborah Kerr, has some serious obsession issues. First, she seems to fall in love with the children's uncle (Michael Redgrave in the film) after meeting him once, for a short amount of time. Then she falls in love with little Miles (Martin Stephens) and Flora (Pamela Franklin). She has known Miles for all of a half hour before she is ready to go to his school and fight for his honor. She uses all of the ghost talk as a way to play an important role in all of their lives; as a way to bring them all together. She needs these people and is willing to do what it takes to have them, to make them love her.
Stir all of this imagination and obsession together, and you get a governess who has gone over the edge. She simply loses it. She is desperate, and lonely; and then she loses it. That is the reality. It happens. Maybe reality is scary enough without ghosts. I think so. Boo.