This past February marked the three-year anniversary of the theatrical release of Annihilation. Adapted from Jeff VanderMeer's book of the same name (which in itself served as the first in a trilogy of books by VanderMeer), the film focuses on a group of explorers who come together to investigate aliens in a mysterious otherworldly zone called The Shimmer.

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Polarizing upon its release, Annihilation is fondly remembered three years later as something of a cult classic and audiences continue to sing its high praises. The movie as a whole has been dissected and analyzed to death for its hidden meanings, but the most interesting aspects of the movie are those that took place behind the camera during the making of it all.

10 Garland Finished The Script Before The Books Were Finished

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In the first book of the Southern Reach trilogy, Annihilation follows Lena and Dr. Ventress. Their ethnicities are not concretely described in the first book, but in later books, it is made clear that they are Asian and half-Native American.

This grew complicated in the filmmaking process as Alex Garland finished the script for Annihilation before the second book in the trilogy even published and cast his actors based on the best actors he found during the casting process. Before Garland cleared things up, fans complained that the movie's character's races were not being accurate to the book.

9 Garland Did Not Reread The Book While Making The Movie

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Even if the races of those characters were clearly defined in the first book, there is a good chance that Alex Garland may not have remembered that detail anyway since while making and writing the movie, he refused to reread the book.

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He opted not to because he did not want to be influenced by the book while creating the cinematic version. That's the same reason why he opted to never read the sequels to the book. Instead, he preferred to adapt it "like a dream of the book," basing his interpretations solely on memory.

8 Stalker Is A Source Of Inspiration

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In an interview with Jason Gorber of That Shelf, director Alex Garland was asked if there was any movie that Annihilation echoes, and Garland said that one movie that sci-fi fans are most likely to notice parallels for is Stalker, directed by Andrei Tarkovsky in 1979. This movie has since been noted for its parallels to Tarkovsky's work by several critics.

What makes this comment so interesting is that the author of the original book completely dismisses such parallels, going as far as to tweet in 2016 that "Annihilation is 100% NOT a tribute to [Stalker]."

7 Natalie Portman Broke Her "No Horror" Rule For This

Natalie Portman in V for Vendetta

In the past, pre-2010, Natalie Portman famously made it clear in a number of interviews that she had no interest in starring in horror movies. She broke her no-horror streak with Black Swan. Obviously, that paid off for her in the form of an Oscar, but beyond that, she seemed adamant about keeping that streak alive.

Her streak continued until the script for Annihilation came to her doorstep. Apparently, beyond the movie's horror-sci-fi premise, she was mostly just interested in working with the people behind the movie, particularly Alex Garland who at the time was off the heels of the critically acclaimed Ex Machina.

6 Annihilation Kept Her From Starring In Another Horror Movie

book cover for pride and prejudice and zombies

With that said, Annihilation technically was not the first movie to break her no-horror movie rule. Prior to being asked to join the cast of Annihilation, Natalie Portman actually auditioned for and won a role in Pride and Prejudice and Zombies, which she planned to star in and produce as early as 2009.

However, as the project slipped further into development hell, this gave Portman time to distance herself from the project and allowed her the chance to accept Annihilation instead. It turned out Portman may have dodged a bullet there since Zombies wound up being a box office flop.

5 There's A Henrietta Lacks Reference

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For those unfamiliar with who she is, Henrietta Lacks was a 31-year old woman who died from cervical cancer and whose cells were —without her consent prior to her death— used to craft the first immortalized human cell line, later referred to in research as HeLa cells. Her life is detailed more thoroughly in the 2017 movie, The Immortal Life of Henrietta Lacks.

Lacks and her cells are subtly referenced in Annihilation in a scene where during Lena's lecture, she describes cells in her video presentation as being based around cervical cancer from a 31-year old patient.

4 Oscar Isaac Pulled Double Duty

Poe Dameron walking from X-Wing in The Force Awakens

Ever since he first found his breakout into the Hollywood scene, it looks as if Oscar Isaac never stops working, to the point that there have been years where he starred in multiple movies in the span of just one year. Annihilation was no different. Not only because he appeared in five movies that same year, but he pulled double duty on the studio lot.

The other movie he filmed right next to Annihilation was Star Wars: Episode VIII - The Last Jedi. Oftentimes, Isaac would have to film scenes for both movies back to back on the same day, hence why he used the same trailer for both movies.

3 Alex Garland Hid One Of The Monsters Until Filming

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One of the movie's more memorable moments is a scene where one of the monsters provides a jump scare that petrified the characters. It's memorable because fans take note of the genuine terror in the face of the actors. If their expressions looked genuine, that's because they were.

Natalie Portman confirmed in an interview with Collider that director Garland had hidden said monster on the set of the movie and didn't unleash it until they started filming, not saying when it would pop out. Portman and co. knew a monster was coming, but they expected more of a CGI effect before being greeted by a more practical beast unexpectedly once the cameras started rolling.

2 It Almost Got Severely Cut

Natalie Portman Oscar Isaac Annihilation

Annihilation itself remained polarizing upon its release. Fans either love it or hate it. Such a mixed reaction was reflected in its test screenings. Based on audience reaction, David Ellison at Paramount felt as though the movie was becoming "too complicated." He wanted director Alex Garland to make some changes to the script that could make the movie more appealing to a mass audience.

Garland really didn't want to make any changes to his movie, and to his relief, producer Scott Rudin supported his decision. Since Rudin had the final cut, not a single thing in the movie was altered or re-shot before it hit theaters.

1 Producer-Director Disagreements Led To Netflix Deal

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Although Alex Garland and Co. were able to have their way with the final cut and got their wish to keep the movie intact, this was not the end of this studio vs. director/producer conflict. Apparently, the studio's concerns persisted in the build-up to the theatrical release and as a result, an almost unheard-of deal was made with Netflix.

It was announced in December 2017 that whilst coinciding with its theatrical release, Annihilation would be streamed internationally through Netflix just 17 days after it hit theaters. It's interesting how this deal parallels how HBO Max would distribute its movies in 2020-21 amid the COVID-19 pandemic.

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