One of my favorite Stephen King works is the novella Apt Pupil. Avoid the movie: it sucks. I think it was a victim of a strained attempt at a happy ending. The novella is much better.
Nothing creeped me out more in the story than when Morris Heisel, curious in an almost crazy way by the way Arthur Denker said the phrase, “You must tell us all about it. Omit nothing”, finally remembers who from his past spoke in that same manner–Kurt Dussander, the death camp commandant responsible for the murder of Heisel’s family.