I think Kafka's Trial is far creepier than Metamorphosis, and a more important work.
It has its points about change in general though.
In the same vein, I recently saw the early bbc performance of 1984, so effectively done it upset people in 1954.
Peter Cushing, produced by Rudolph Cartier who had fled the nazis, it is a superb interpretation.
It's been many years since I read the book, but i think it may be becoming more important as years go by, rather than less, especially with his emphasis on thought control by limiting language.
http://en.wikipedia.org/wiki/Nineteen_E ... _programme)
I'm going to have to re-read it, but it has come back to me surprisingly well.