Annihilation

The film opens on Lena — a biologist and former soldier — being debriefed inside a hazmat facility. She is the only one who came back. The story unfolds as her account.

Lena's husband Kane, a soldier, disappeared on a classified mission a year earlier. Then he reappears at their home — present but hollow, unable to remember how he returned. He rapidly deteriorates. Government vehicles intercept their ambulance and deliver them to a facility called the Southern Reach, on the edge of a quarantined coastal zone designated Area X.

Dr. Ventress, a psychologist who has been running expeditions into the Shimmer, is assembling another team. The Shimmer is an opalescent, expanding boundary that appeared around a lighthouse several years ago. Every team sent in has never returned. Lena volunteers. The others — paramedic Anya, physicist Josie Radek, geologist Cassie Sheppard — are all damaged in their own ways. Ventress tells Lena later that self-destructive people are the ones who keep volunteering.

Inside the Shimmer, the team discovers it refracts everything — radio signals, GPS, light, and DNA. Plants grow in the shapes of human bodies. Animals carry spliced human genetic material. The women are changing too, their cells already rewriting themselves. Cassie Sheppard is taken and killed by a mutant bear whose roar carries the dying sound of a previous victim's voice. When the bear attacks the camp, it screams in Sheppard's own voice as it kills her.

Anya, growing paranoid and violent, restrains the others — convinced they are being transformed and cannot be trusted. She is later found dead near the lighthouse base, killed by something they never identify. Josie Radek, who has self-harm scars on her arms and seems drawn to what the Shimmer is offering, walks alone into the garden and lets it take her — her body dissolving into one of the human-shaped flowers rooted in the earth.

Ventress and Lena reach the lighthouse alone. Beneath it, in a flooded chamber, Ventress is consumed by a pulsing mass of alien light. Something emerges from it — formless at first, then beginning to mirror Lena's every movement. It takes on a shining, humanoid shape in her image. Lena is unable to fight it. She places a phosphorus grenade in its hands. It burns, still mirroring her — and destroys itself along with the lighthouse. The Shimmer collapses.