Photos |  Paramount Pictures / Universal Pictures

FROM LEFT: In “Annihilation,” Natalie Portman stars as a biologist who leads a dangerous, secret expedition into a mysterious zone where the laws of nature don’t apply. When Jurassic World’s dormant volcano begins roaring to life, Owen (Chris Pratt) and Claire (Bryce Dallas Howard) mount a campaign to rescue the remaining dinosaurs from this extinction-level event.

Novelist turned screenwriter Alex Garland explored what lies beneath human flesh in 2014’s “Ex Machina,” and he digs under our skin again with “Annihilation,” starring Natalie Portman and Oscar Isaac. In the former, the possibilities of artificial intelligence dangerously beguiled as a substitution for humanity as we know it. In “Annihilation,” a possibly alien presence, known as “The Shimmer,” is out to remake our world.

Portman stars as Lena, a biologist and former soldier whose husband (Isaac) is still active duty and, when the film opens, missing for over a year. He staggers home one night but their reunion is short-lived; soon he is in a coma, and Lena is on a secret military base where the affectless, quietly sinister Dr. Ventress (Jennifer Jason Leigh) lays out some rather dire facts.

An ever-increasing section of Florida has been lost to something they call “The Shimmer,” which began at a lighthouse and is spreading its inexplicable influence farther and farther. None of the military teams they have sent in to find answers have returned — except for one guy, and we know who that is. Lena decides to join the next team, composed somewhat arbitrarily of Dr. Ventress, who is a psychologist, a young physicist (Tessa Thompson) and two other tough ladies, each with their own “nothin’ to lose” backstory.

I have to say, I found the government’s response to this “Shimmer” rather slapdash. Not so much as a drone has emerged from “The Shimmer,” yet they accept volunteers for the mission like it was a beer run, and once inside express surprise when everything tries to kill them and none of their stuff works. Science fiction movies must adhere to their invented logic, and it’s frustrating when they don’t. Sometimes the mysteries of “Annihilation” can be too opaque.   

Steamy Florida seems the perfect place for “The Shimmer,” as biological aberrations become increasingly obvious and disturbing. At first we see beautiful flowers growing everywhere, but there’s something wrong, too, as it appears every different kind of plant is growing from the same vine. Soon, the women meet a fearsome alligator with the same sort of biological changes.

“Annihilation” features two kinds of special-effects scenes, scary then trippy, and both are indelible. First, there are a couple of memorable, viscerally horrifying things that happen that are truly frightening, especially a bearlike monster who shrieks in the voices of the characters he has previously devoured, and this is a skin-crawling terror of the highest caliber.

The climax of the film takes place when some characters — you won’t be too shocked to learn that not everyone makes it all the way — reach the lighthouse, and the trippy stuff begins. I have a low tolerance for this kind of thing, but I actually found this sequence interesting, beautiful and, for a mind-bending science fiction flick, satisfying. Less cantankerous viewers should like it even more.

This film reminded me, in both pace and subject, of 2016’s “Arrival.” In both films, a female scientist cautiously and intellectually approaches the inexplicable when it comes to call from lands beyond. Ultimately, I prefer “Arrival,” but “Annihilation” is more exciting, scary and gross, in a good way. It is based on the novel by Jeff VanderMeer, and the journey from page to screen has certainly delivered some intense physical, visual moments.

Some weird problems with the release of the film have led it to be sold to Netflix, so you can rent it or stream it there, and, due to a mercifully sane run length, I think it would actually benefit from multiple viewings. “Annihilation” is cerebral, but even more, it is fleshy and makes your skin crawl, and those moments are even more effective than the mind-bending ones.