Nocturnal Animals is one of my favorite films of 2016, and immediately upon having seen it, I made my way to the bookstore and picked up a copy of the source novel. I can't wait to compare the two and see what was reworked to make the story more cinematic (if anything), and make an assessment as to what I would have done different (if anything). Please note that I haven't read the corresponding books of all of the below listed films, because my time on earth is finite and reading takes a long time. Anywho, here are some of my favorite book-to-film adaptations!
The Rules of Attraction (2002 - Dir. Roger Avary)
This adaptation of the 1987 novel by Bret Easton Ellis takes the core tale of a bunch of hard partying rich kids and brings it to the present day. Existing in a post-American Pie landscape, Attraction is a subversion of the sexually-charged fun that fueled the teen comedies of the early aughts. It's also funnier than any of them. The alterations from the book are mostly in the form of streamlining, which places some of the more specific events into a delicious ambiguity.
Sorcerer (1977 - Dir. William Friedkin)
The source novel La Salaire de la Peur has been adapted twice now, and despite being labeled as such, Friedkin insists that his take on the story is a direct adaptation, and not a remake of the first film. This is, by its very nature, one of the most intense films ever made, as the centerpiece is a supremely volatile stash of nitroglycerin. Anyone who's played Crash Bandicoot knows that even the slightest touch can set off the explosives, and Sorcerer puts these explosives on a trek through a perilous jungle by way of a rickety truck. The film is broken into 4 parts, each with a title card, which is suggestive of the novel's structure (presumably). The dialogue is sparse, with most of the acting done through sweaty-faced brooding (a domain over which Roy Scheider is king), which also hints at a novel lush with page-turning detail. Death Sentence (2007 - Dir. James Wan)
Upon release, Death Sentence was heralded as "Death Wish, but with Kevin Bacon." Well, that's pretty much what it is. Death Sentence is based on a novel of the same name written by Brian Garfield, who also wrote, you guessed it: Death Wish. Unlike the classic Bronson flick, which mostly advocates the use of vigilante justice, Death Sentence maintains Garfield's anti-violence message (without forgoing a few excellent sequences of glorious, glorious violence). Garfield praised the adaptation of his novel for this very reason, citing that Kevin Bacon's portrayal of a man's descent into the self-destructive nature of vigilantism rings true with the themes of his novel.
A History of Violence (2005 - Dir. David Cronenberg)
There is a supremely twisted body-horror scene in the graphic novel upon which this film is based, and when I saw that Cronenberg would be helming the film adaptation, I couldn't wait to see how it would be handled by the master. Once the movie started it became clear that the Cronenberg of Videodrome had matured, making way for a stronger, more subdued storyteller. Unfortunately, my favorite gross-out scene from the novel had been excised entirely, but so had much of the story. By reworking the titular history, Josh Olson's screenplay finds a thematically richer, more adult story contained in the same shell. This is one of those rare cases where the film is superior to the book, even though the book is excellent.
Die Hard (1988 - John McTiernan)
Every character in Die Hard has an arc. Every. Single. One. I've never read the book (Nothing Lasts Forever) because I don't have to. Because Die Hard. Is it a great adaptation? Duh. Because Die Hard. Is it better than the book? Die Hard. Are you not a fan of Die Hard? DIE. HARD!