The Rambo Movies
First Blood is a somber reflection of the hardships that faced Vietnam War veterans upon their return to their native country, in which the protagonist blows up a helicopter with a freaking rock.
No really. There were Rambo books. Seriously. No, they weren't composed entirely of onomatopoeias meant to represent the sound of explosions.
First Blood was written by author David Morrell, who wrote a lot of books that had pictures of knives on the cover.
In the book, Rambo is not the good guy, as he basically flips out and kills a whole town because the Vietnam War drove him insane. Also, the book's ending is depressing, as Rambo stops his totally awesome rampage to be shot in the face.
That's right; Rambo dies at the end. Hollywood decided to change that, too, paving the way for three sequels. Even stranger, Morrell wrote a sequel to the book to coincide with the film, which somehow portrays Rambo as still alive, without so much as an opening chapter where a necromancer summons him from Valhalla.
For the book version of Rambo: First Blood Part II The writer had to share a co-author credit with James Cameron and Sly Stallone (who helped dream up the story for the sequel) which is kind of sad, or not, depending on how much he got paid.
Yes, The Thing. The one where the guy's torso grows teeth and bites another guy's arms off.
It was actually a novella (that's where the writer didn't feel like writing a whole novel and just wrote part of one) called Who Goes There? and it was written way back in 1938 by John W. Campbell (the whole thing is online here). Yes, it even has that scene where they're poking at the blood and it comes to life and goes flying out of the dish and we poop our pants.
It's considered one of the best science fiction novellas ever written, and you can thank the writer for all those elements of paranoia and tension that made the film great. On the other hand, the movie has that scene where a guy's head turns into a crawling spider monster and you probably need to see that one to get the full effect. Also, Kurt Russell.