Annihilation Movie Explained

Annihilation - (2018) - Written and Directed by Alex Garland

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An asteroid with alien life on it (like panspermia) crashes to earth into a lighthouse in Florida. This alien life form is intelligent (possibly even highly advanced artificial intelligence), and it can take control of other organisms' DNA. It can instantly genetically modify the organism by editing its DNA and swapping it with other species to create entire new hybrid organisms.

The alien life form exists in a rainbow bubble called the shimmer. The shimmer slowly expands as the alien life form takes control over more and more plants and animals around the lighthouse.

The government sets up a base to try to contain the shimmer. They send in teams of soldiers, but none of them come back ... until Kane (Oscar Isaac). He returns home after a year to his wife Lena (Natalie Portman), but she realizes something is off. Kane looks like Kane, but he does not act like Kane.

Lena (a former soldier and current biologist) volunteers to go into the shimmer with a new team of four other women to find out what’s going on. She and the other women start getting their minds and bodies messed with by the shimmer (or the alien life form). It swaps their DNA with other organisms: plants, trees, bears, alligators, sharks, and even each other. For instance, it swaps Anya's (Gina Rodriguez) ouroboros tattoo with Lena. And the bear has Cass's (Tuva Novotny) voice after killing her. And Josie (Tessa Thompson) starts growing plants out of her veins.

One by one, the team is taken out. Eventually, Lena goes to the lighthouse alone. She first discovers a video showing that the real Kane died—killed himself with a grenade—and the Kane who escaped the shimmer was an alien clone.

In a hole under the lighthouse, some kind of alien hive, Lena discovers Dr. Ventress (Jennifer Jason Leigh) the psychologist and leader of the group. She explains how the alien doesn’t want anything. It's not evil. It has no plans to kill humans or take over the world. It's simply curious. It wants to create. That's what it's doing by genetically editing the various organisms in the shimmer. It's taking over evolution, creating new life.

Dr. Ventress is completely overtaken by the alien, which then takes a drop of Lena's blood and uses it to replicate and create a copy of her, just like it did to her husband, Kane. It's an exact replica that mimics her actions. Lena tries to escape, then uses a grenade to kill her doppelgänger, and with it, all the other organisms it was controlling inside the shimmer.

But the copy of Kane back in the government base remains alive when Lena returns. She is the real Lena (not an alien clone), but she is still infected with the shimmer—or permanently genetically modified. For instance, she still has Anya's tattoo.

The biggest mystery is why did Kane not die when the other alien-controlled organisms died? Is it because he was outside the shimmer? Or is he a separate alien life form? Were there two of them on the asteroid, each controlling different organisms? What are clone-Kane's plans? Does he/it have the ability to edit the genes of other organisms? Will more asteroids containing these aliens land on earth?

These questions are deftly left unanswered, open to interpretation by the viewer. What do you think?