Garland's first movie since "Ex Machina" is extremely violent and one hell of a mental workout.

Alex Garland’s highly anticipated new film “Annihilation” has begun screening for press, and the first group of reactions shared online are extremely enthusiastic. The film is based on the novel by Jeff VanderMeer and marks Garland’s first directorial effort since breaking out with “Ex Machina.” Natalie Portman stars as a biologist who joins a team of female scientists on a mission inside an environmental disaster zone known as Area X. Jennifer Jason Leigh, Tessa Thompson, Gina Rodriguez, and Oscar Isaac so-star.

Anyone familiar with Garland’s brand of disturbing and head-spinning science-fiction (he wrote “28 Days Later” and “Sunshine”) will find much to love in “Annihilation.” Without saying too much, the film is the best kind of challenge and it represents the type of brainy, violent science-fiction most studios wouldn’t dare touch these days. There’s a reason the first round of reactions includes praise like “brilliant,” “riveting,” and “wickedly disturbing.”

“Annihilation” opens in theaters nationwide February 23. Check out the first reactions below.

ANNHILATION is, in wholly inelegant terms, one hell of a mindfuck. Most of the time, I didn’t want it to end; occasionally, I was so unsettled I thought I might keel over. — Kate Erbland (@katerbland) February 8, 2018

#Annihilation is big budget Alex Garland with all the head-spinning intelligence of “Ex Machina.” It’s violent and patient and then suddenly so transfixing you’re pinned to your seat. It’ll take time to process. Another auteur studio gamble from Paramoint after “mother!” — Zack Sharf (@ZSharf) February 8, 2018

Make no mistake, #Annihilation is a new sci-fi classic. Brilliant, thrilling, and provocative, it has as much metaphoric depth as it does narrative tension. I’m floored. pic.twitter.com/o2taDg2Z7L — Drew Taylor (@DrewTailored) February 8, 2018

#ANNIHILATION: This is the type of sci-if we always say we want to see. Bold, challenging, singular, visually dazzling. Would not be the least bit surprised to see it hailed as a masterpiece (and it might actually be one). — Ben Pearson (@benpears) February 8, 2018

Alex Garland’s #Annihilation is another example of the kind of brainy sci-fi we don’t see enough of. Badass female cast and a story that’s both beautiful and wickedly disturbing, and an ending you will talk about for days. Dug it so much pic.twitter.com/fW77z6xX4v — ErikDavis (@ErikDavis) February 8, 2018

Alex Garland’s #Annihilation is absolutely phenomenal. It’s gorgeous and mesmerizing, with brilliant performances from the entire ensemble. It’s a remarkable vision, and has a sequence so thrilling that I was left literally dizzy. It will be on my Top 10 of 2018 without question. pic.twitter.com/zGmDGlyh0M — Eric Eisenberg (@eeisenberg) February 8, 2018

Just saw #Annihilation, and damn, it’s gorgeous. Beautifully done, riveting and smart. Going to need to process this one for a while, and I want to see it again! pic.twitter.com/rFl5cnacon — Jenna Busch (@JennaBusch) February 8, 2018

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