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Stowaway

Stowaway 2021

Directed by

Joe Penna

Joe Penna

Made by

Netflix

Netflix

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Plot Summary

Read the complete plot summary and ending explained for Stowaway (2021). From turning points to emotional moments, uncover what really happened and why it matters.


The crew of the MTS-42 is on a pivotal journey to Mars, comprising commander Marina Barnett (played by Toni Collette), biologist David Kim (portrayed by Daniel Dae Kim), and medical researcher Zoe Levenson (acted by Anna Kendrick). As the mission launches, Marina notices a slight underperformance in the ship’s main engines; however, Hyperion’s mission control reassures her that there is enough fuel to counteract the issue. Driven by her instincts, she holds off on using the final abort window, aware that this is her third and last mission after two previous ones.

David, focusing on vital research to sustain human life on Mars, views this mission as the first step towards transforming the planet into a second home for humanity. After launching, the vehicle docks with a space station that will be their home during the nine-month journey. The crew takes command of the MTS-Cycler, a station built over successive missions that utilizes its upper stage fuel tank tied to tethers, functioning as a counterweight for inertia-based artificial gravity. David and Zoe, hailing from Harvard and Yale respectively, develop a friendly rivalry as they navigate their tasks.

Soon after takeoff, Marina discovers Michael Adams (played by Shamier Anderson), a stowaway engineer who has been injured and is unconscious behind a panel. Grabbing her medical skills, Zoe quickly stitches him up and manages to save his life with the help of 3D printed parts, though Marina suffers some bruising. Michael, in a state of panic after realizing he had launched twelve hours prior, struggles with the realization that he can’t return to his sister. Fortunately, Marina informs him that Hyperion has arranged for a nanny to take care of her.

As the mission unfolds, unexpected challenges arise. Michael’s arrival inadvertently compromises critical ship functions when his body damages an essential device that scrubs carbon dioxide from the air, leading to a breach in the life support module. With a grim reality setting in, they realize the sealed-off section leaves only one module an option that is shielded against solar radiation storms.

Taking Michael under his wing, David tasks him with handling data for research tests, but the deteriorating conditions force the crew to resort to emergency lithium hydroxide canisters for CO2 scrubbing, which are limited in sustaining enough oxygen for all four crew members. Burdened with the responsibility of survival, Marina insists that David cultivate his algae experiment immediately, despite the lack of proper supplies, since it is their only chance for long-term oxygen provision.

As time is of the essence, tensions mount among the crew. Although David is hesitant due to missing vital equipment sent ahead to Mars, Marina presses him to activate the algae that can yield sufficient oxygen. With only partial success, the survival stakes climb ever higher; the situation quickly devolves with oxygen quantities dwindling as they push to salvage their mission.

Desperate for solutions, Marina contacts mission control for guidance. However, their only option—a perilous EVA to retrieve oxygen from the launch vehicle—is deemed too risky, leaving Barnett and David contemplating the harsh reality of sacrificing Michael. Their hope flickers as Zoe persuades them to wait, explaining they have a buffer of twenty days and urging to hold on for assistance.

After a heart-wrenching three days of tension, David bravely opens up to Michael, offering him a painless exit. Nearly succumbing to despair, Michael hesitates only to be encouraged by Zoe, who remains steadfast in saving him. With determination, she opts to scale the tethers to reclaim the needed liquid oxygen herself, with David reluctantly agreeing to join her.

Facing deadly conditions during their EVA, they manage to fill two oxygen tanks, essential for survival. Yet, facing a deadly solar flare, they are forced to leave one behind. Upon their return, Zoe accidentally drops the filled tank, wasting their hard-earned efforts and suggesting bleak outcomes as the launch tank begins to leak.

Realization hits hard: one must brave the fray to secure their remaining chance at survival. With nobility, Michael, David, and Zoe all volunteer for this ultimate sacrifice, yet Zoe firmly insists on being the one to retrieve the tank from the launch vehicle. Battling against all odds, she succeeds but ultimately succumbs to radiation—her final moments filled with the awe of Mars glistening amongst the stars, reminding them all of the dream that once united their journey.

Timeline

Follow the complete movie timeline of Stowaway (2021) with every major event in chronological order. Great for understanding complex plots and story progression.


Mission Launch

The crew of MTS-42, led by Commander Marina Barnett, embarks on a critical mission to Mars. Despite noticing an issue with the ship's engines, mission control assures her of the fuel reserves, prompting her to proceed with the launch.

Launch Day Earth

Docking with MTS-Cycler

After launch, the MTS-42 docks with the MTS-Cycler, a space station designed for their nine-month journey. This station, utilizing its upper stage fuel tank as a counterweight, creates an environment mimicking artificial gravity.

Post-Launch Space

Discovery of Stowaway

While conducting routine checks, Marina discovers Michael Adams, an injured stowaway, hiding aboard the ship. Zoe, leveraging her medical expertise, rushes to provide first aid to Michael, saving his life despite suffering minor injuries herself.

Shortly After Docking MTS-42

Life Support Compromised

As the crew adjusts to their mission, they face disaster when Michael inadvertently damages the CO2 scrubber, causing a breach in the life support module. This incident puts the crew's survival in jeopardy, forcing them to rethink their resources.

Days After Stowaway Incident MTS-42

Algae Experiment Pressed

With dwindling oxygen levels, Marina insists David activate his algae experiment, which they hope will provide a sustainable oxygen source. Despite the lack of adequate supplies, the crew understands this could be their last chance to secure long-term survival.

As Oxygen Levels Drop MTS-42

Desperate Measures

As tensions rise within the confined quarters, Marina contacts mission control for possible solutions. The team discusses a risky option of retrieving oxygen directly from the launch vehicle, but the dangers involved add to the mounting pressure.

Amidst Oxygen Crisis Communication with Mission Control

Emotional Confrontation

In a moment of desperation, David offers Michael a way out, hinting at a sacrifice for the sake of the crew's survival. This difficult conversation weighs heavily on the team, as they grapple with the reality of their dire situation.

Three Days After CO2 Scrubbing Failure MTS-42

EVA Mission Planned

Zoe proposes a bold plan to retrieve liquid oxygen by performing an extravehicular activity (EVA) to the launch vehicle. Though risks are involved, her unwavering resolve inspires the crew to take action in hope of survival.

Before EVA Deployment External to MTS-42

EVA Execution

Zoe and David embark on the EVA under hazardous conditions, successfully filling two oxygen tanks essential for their survival. However, a solar flare forces them to make a difficult decision, leaving one of the filled tanks behind.

During EVA Outside MTS-42

Oxygen Tank Mishap

Upon their return, disaster strikes as Zoe accidentally drops one of the filled tanks, rendering their hard-earned effort worthless. The severity of their situation becomes painfully clear, adding to the crew’s mounting despair.

Post-EVA Return MTS-42

Ultimate Sacrifice

As the crew faces their ultimate trial, Michael, David, and Zoe volunteer for a final act of bravery to recover the remaining oxygen tank. However, Zoe resolutely insists she will undertake the perilous task herself to save them all.

Before Final EVA MTS-42

Zoe's Final Moments

Zoe successfully retrieves the tank but succumbs to lethal radiation during her return. In her last moments, she gazes at the beauty of Mars against the stars, encapsulating the dream that brought them together on this fateful journey.

During Final EVA Space

Characters

Explore all characters from Stowaway (2021). Get detailed profiles with their roles, arcs, and key relationships explained.


Zoe Levenson (Anna Kendrick)

Zoe is a determined medical researcher, driven by her commitment to her crew and their survival. Her quick-thinking and medical skills emerge as vital when faced with dire circumstances. Throughout the mission, her bravery and resilience shine as she confronts the potential sacrifices required for survival.

👩‍⚕️ Medical Researcher 💪 Resilient 🌟 Brave

Marina Barnett (Toni Collette)

Marina serves as the mission commander, demonstrating leadership and intuition in critical situations. Her experience and gut feelings guide the crew through numerous challenges, as she battles internal and external pressures. The weight of responsibility is heavy on her shoulders as she navigates life-and-death decisions.

👨‍✈️ Commander 🔑 Leader 🌪️ Determined

David Kim (Daniel Dae Kim)

David is a biologist focused on using science to support human life on Mars. His intellect and research drive the mission's vision, yet he grapples with self-doubt and ethical dilemmas. As tensions rise, David's evolution as a character reflects the need to balance survival instincts with moral considerations.

🔬 Biologist 📊 Researcher 🤔 Ethical Dilemma

Michael Adams (Shamier Anderson)

Michael, a stowaway engineer, finds himself caught in a life-threatening situation. Initially panicked and uncertain, his character develops as he steps up to contribute despite the chaos surrounding him. Michael's journey embodies the struggle to adapt and survive in an unforgiving environment.

🛠️ Engineer 😰 Panicked ⚡ Adaptable

Setting

Learn where and when Stowaway (2021) takes place. Explore the film’s settings, era, and how they shape the narrative.


Time period

The timeline is set in a near-future context where space travel has advanced significantly. Humanity is seeking to establish a sustainable presence on Mars, a pivotal era for colonization and survival beyond Earth. The mission underscores both the technological advances and the challenges of human space exploration.

Location

MTS-42, MTS-Cycler, Mars

The MTS-42 is a spacecraft on a mission to Mars, showcasing advanced technology for deep space travel. The MTS-Cycler serves as a space station crucial for the crew's nine-month journey, designed for inertia-based artificial gravity. Mars, the mission's destination, is viewed as a potential second home for humanity, embodying hope and exploration.

🌌 Space 🛰️ Space Station 🌍 Mars

Themes

Discover the main themes in Stowaway (2021). Analyze the deeper meanings, emotional layers, and social commentary behind the film.


🧑‍🚀

Survival

The movie explores the theme of survival in extreme conditions against the backdrop of space. The crew faces dwindling oxygen and life support failures, highlighting their desperate struggle to live. Personal sacrifices and difficult decisions bring the narrative to focus on the will to survive against all odds.

🤝

Teamwork

Teamwork is vital in the face of adversity as crew members must rely on each other’s expertise and strengths. The relationship dynamics reflect the necessity of collaboration, particularly in life-and-death scenarios. Despite tensions, their bonds grow stronger as they collectively face overwhelming challenges.

🌌

Exploration

The pursuit of exploration and the human spirit's indomitable curiosity drive the narrative. The mission to Mars symbolizes hope for the future and the desire to conquer new frontiers. It delves into the aspirations of transforming alien worlds into a new human habitat.

Stowaway Ending Explained

Unravel the ending of Stowaway (2021) with our detailed explanation. Understand the final scenes, character fates, and unresolved questions.


In the end, Zoe makes a brave and ultimately sacrificial choice to go outside the ship in space, risking her life to retrieve a crucial oxygen cylinder that had been lost. Her daring act is driven by her desire to save her crew, knowing that the oxygen supply is too limited to sustain all four of them. By risking her life, she manages to bring back the cylinder, which helps prolong the ship’s and the crew’s survival. Unfortunately, her sacrifice isn’t enough to save herself, and she succumbs to the extreme radiation exposure caused by her outside work. The ending underscores the harsh human cost of making impossible choices in life-threatening situations, emphasizing her bravery in the face of imminent death. Ultimately, her selfless act ensures that her fellow crew members can continue their mission and achieve some hope of survival against overwhelming odds. Meanwhile, the other crew members are faced with the reality of their dwindling resources and the impossible dilemma of who will survive and who won’t—highlighting the brutal moral and existential questions that space tragedies often evoke. In the final moments, the story leaves us with a powerful reminder of the sacrifices made in extreme circumstances and the tragic cost of prioritizing one life over another.

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