Annihilation, inspired by author Jeff VanderMeer’s award-winning novel of the same name, is an ambitious, provocative, and visually sumptuous sci-fi thriller. It boasts a rock-solid cast, an inspired soundscape, and wonderful world-building, though it falls a bit flat in the home stretch.

Perhaps most important to Annihilation’s success was creating the Shimmer, the threatening area that a team of scientists led by Lena (Natalie Portman) cautiously explore. Mother Nature is running amok in the Shimmer, and the results are both monstrous and breathtaking. The surface of the Shimmer looks like a soap bubble: Rainbows are reflected on surfaces and refracted through all the light coming in. Pastel mold and fungi playfully dot trees and eerily explode out of corpses. The candy-colored tones of this world communicate a Wonka-like whimsy, but an undertone of menace is always present thanks to the constant hum of unsettling noises created by the movie’s sound team. The Shimmer is always buzzing, creaking, moaning, or reverberating with thunder-like rumbles, signaling its constant state of creation. The soundtrack transitions between the twangs of the Crosby, Stills & Nash song “Helplessly Hoping” and orchestral arrangements layered with synth patches and otherworldly manipulated vocal effects. This creates a sonic separation between humanity and nature as we know it, and the gorgeously grotesque Shimmer that intensifies the further the team journeys into it.

Ignoring director Alex Garland’s boneheaded mistake to not bother reading book two in VanderMeer’s Southern Reach trilogy—in which it’s revealed that Portman’s character is of Asian descent and Jennifer Jason Leigh’s aloof psychologist is half Native American—the five women who form the core of the cast give excellent performances. Much of the film’s conflict stems from paranoia, waning sanity, and perceiving the inconceivable, so the actresses’ ability to convey internal struggles, revelations, and terror through their eyes and facial expression is crucial. The team is different from the one in the book, and Gina Rodriguez’s paramedic Anya is a welcome addition to the mix. Rodriguez brings physicality and swagger to her role that helps balance the coolheaded academics on the team—until her emotions overwhelm her in an arresting mental-breakdown scene. All five women succeed at giving the audience glimpses of human self-destruction in distinct ways.

As far as plot goes, Garland took the DNA of VanderMeer’s book and then evolved and mutated many aspects of it. The movie’s major themes are communicated in subtle ways, as well as through awkward direct statements that are somewhat insulting to the audience’s intelligence. Annihilation does encourage a second viewing to spot symbols and clues that provide additional layers of meaning to the movie, such as an arm-hopping tattoo of a snake eating its own tail. Unfortunately, the film’s climactic confrontation scene is a bit of a record scratch, breaking the Shimmer’s spell on the viewer. This partly stems from the presence of a humanoid being that is supposed to be creepy and captivating, but looks more like a person in a lycra bodysuit.

Besides this misstep and a few weak points in the character development, Annihilation conveys a mesmerizing concept by building a haunting world that forces its characters to confront abstract ideas about identity, human nature, and creation, but doesn’t guarantee them answers. For fans of the book series, the standalone film’s convenient ending seemingly closes the door to any potential sequels.