The six-person crew aboard the International Space Station (ISS) embarks on an extraordinary mission when they capture a probe returning from Mars, which carries a soil sample that could potentially harbor signs of extraterrestrial life. With the ISS having spent an astonishing 30 years in orbit and amassing a cost of $200 billion, the stakes are incredibly high. The pilgrim capsule, traveling for eight months, becomes damaged by debris and veers off its intended path.

The fearless astronaut and engineer, Rory Adams, takes on the challenge of venturing outside the ISS to secure the capsule using the station’s robotic arm, all while facing immense peril. His instructions dictate that if he cannot successfully capture it, he must push the capsule into the vast expanse of space. With deft precision, the ISS fires its thrusters to position itself appropriately, allowing Rory to accomplish this daunting task of capturing the probe.

On the second day, the soil sample is transferred to a quarantine lab for rigorous experimentation. Here, exobiologist Hugh Derry successfully revives a dormant cell from the sample, which flourishes in a high CO2 atmosphere with minimal oxygen and a nutrient-rich glucose medium at a comfortable temperature of 20 degrees Celsius. This remarkable discovery stands as the first definitive evidence of life beyond our planet, quickly evolving into a multi-celled organism dubbed “Calvin” by American school children.

As the days unfold, we realize the toll that space has taken on astronaut David, portrayed by [Jake Gyllenhaal], who has been in orbit for an astounding 473 days, causing severe muscle atrophy and exposing him to the maximum allowable radiation. By the twelfth day, Hugh uncovers the astounding adaptability of Calvin’s cells, which can transform to function as muscle, neurons, and photo-sensory cells simultaneously. Calvin begins developing appendages and engages with Hugh, forming unsettling bonds.

However, on day twenty-five, an atmospheric mishap in the lab sends Calvin into a temporary state of dormancy. While Hugh becomes increasingly emotionally attached to Calvin, commander Katerina expresses relief, fearing the rapid growth of this alien entity. Driven by his emotional connection, Hugh attempts to revive Calvin using mild electric shocks, only to provoke a terrifying response. Calvin becomes hostile, brutally attacking Hugh and escaping from containment.

As Calvin grows more ferocious, he consumes a lab rat before encountering Rory, who bravely enters to save Hugh. Yet, Calvin latches onto Rory’s leg, and Austin command David makes a harrowing choice to lock Rory in the room as a desperate measure to contain the creature. Calvin’s savage nature leads to a gruesome scene where Rory meets his tragic end after battling Calvin with a flamethrower. The creature effectively escapes through a vent, signaling the escalation of chaos aboard the ISS.

With communication to Earth severed, the mission commander, Katerina, executed by Olga Dihovichnaya, bravely conducts a spacewalk to repair the damaged antenna. Unfortunately, she falls victim to Calvin’s predatory instincts, leading to a catastrophic accident that results in her drowning inside her suit as liquid fills her helmet. In the ensuing panic, Calvin makes an attempt to infiltrate the station through the thrusters.

The crew is faced with dire measures, trying to leverage their limited fuel supply to launch Calvin into deep space, but their plans backfire, rendering the ISS to drift into a decaying orbit, risking complete destruction upon re-entry into Earth’s atmosphere. Sho Murakami forewarns the crew about the dwindling options as the ISS struggles and the lurking threat of Calvin looms ever closer.

In a last-ditch attempt for survival, the crew come up with a plan to seal themselves in one module and vent the atmosphere from the rest of the station, hoping to render Calvin inert. However, calamity strikes when Hugh unexpectedly enters cardiac arrest due to Calvin’s attachment to him, leading to horrifying consequences. Now manifested as a colossal, tentacled being, Calvin wreaks havoc among the remaining crew.

The situation grows increasingly desperate as they use Hugh’s lifeless body as bait to divert Calvin while attempting a final stand against the creature’s relentless assault. As a Soyuz capsule approaches for a potential rescue, the crew believes help is at hand, but their optimism rapidly turns to despair as Calvin unleashes chaos, cleaving the capsule away and leading to a crash that decimates their hopes.

Ultimately, only David and Miranda North emerge as survivors from this catastrophic turn of events. With the ISS spiraling towards doom, David hatches a daring plan to transport Calvin into one of the escape pods, while Miranda attempts to escape to Earth in the other. As David valiantly sacrifices himself, launching into the terrifying void of space with the creature, the prospect of Miranda’s survival hangs by a thread.

The fate of David is revealed when he is unearthed near fishermen, his body entangled in a web-like substance that conveys the sheer horror of what has transpired. Meanwhile, Miranda’s pod is tragically diverted into the uncharted depths of space, leaving her own fate uncertain as she disappears from view, while David, still alive, desperately tries to ward off any rescue attempts. The chilling final moments serve as a haunting reminder of the dangers lurking in the unknown corners of our universe.