Annihilation is loosely based on the book of the same name written by Jeff VanderMeer in 2014 as the first novel in a trilogy. I say "loosely based on," and I do mean "loosely. The movie is recognizable as being related to the book, but it departs significantly from the Nebula award winner. I won't try to list all the ways in which the movie differs from the novel, but in broad terms, the character development is significantly different, as is the way in which the story deals with the primary puzzle of what caused the shimmer. In particular, the lead character is almost entirely different from her counterpart in the novels. Additionally, the conclusion is completely different, and seems to have been the result of trying to wrap up the story in a single movie, despite the fact that it took three books to dig deeper into the mystery, and even then the author didn't try to wrap things up in a neat package. Lastly, the movie takes on more of a horror feel than I got with the novel, relying more on scary monsters than the source material did.
If you leave the books aside, this is a solid but not spectacular sci-fi suspense/horror film. The pace is relatively slow, and the dialogue is sparse, but that allows the audience to focus on the environment and the developing psychological stress of the expedition team. Unfortunately, in diverting from the novel, the film turns into a fairly predictable story in which you wait for the next scary scene, count down as the team members die or disappear until only the heroine is left, and then watch as she wraps things up in a pretty blatantly foreshadowed manner. The film looks great. The director did a good job of creating some truly bizarre and beautiful aspects of the changing world inside Area X. The casting was also pretty good, and the actresses who make up the bulk of the cast (there are only 8 speaking roles in the film) do a fine job. Natalie Portman plays the lead, and Jennifer Jason Leigh, Gina Rodriguez, Tessa Thompson, and Tuva Novotny all put in solid performances.
Annihilation has a fair amount of violence, gore, and some foul language. There are a couple of sexually suggestive scenes, but no nudity. It's definitely an adult movie.
Overall, if I hadn't read the book, I imagine that I would have found Annihilation to be a very good but not spectacular sci-fi film. Having read the book, I have a little disappointment, although the changes are understandable given the desire to turn the story into a single film. It actually left me feeling a bit the same as I did after Ex Machina, which was made by the same director. If you're a sci-fi fan, you'll want to go see this movie.
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