Different Seasons (1982) is a collection of four Stephen King novellas with a more dramatic bent, rather than the horror fiction for which King is famous.
Of course the first story was adapted into one of the greatest films of all time, Shawshank Redemption.

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The Body was adapted for Stand by Me (1986). Another of the greatest films of all time.
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I couldn’t really get into the novella, The Body, however.
Instead it was Apt Pupil that really got me.
It’s the story of the evolution of a mass shooter from age-13 to 17.
… student Todd Bowden discovers that his elderly neighbor, Arthur Denker, is Kurt Dussander—a former Nazi concentration camp commandant who is now a fugitive war criminal.
Todd, fascinated with Nazi atrocities perpetrated during World War II, blackmails Dussander, forcing him to share disturbing stories of what it was like working at Nazi extermination camps and how it felt to participate in genocide. …
I’ve not seen the film. 54% on Rotten Tomatoes. Ian McKellen stars as Dussander.
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