At the landing site of the Ares III shuttle on Acidalia Planitia, Mars, amidst a not-so-distant future, the Hermes crew, which includes Commander Melissa Lewis (Jessica Chastain), botanist Mark Watney (Matt Damon), IT specialist Beth Johanssen (Kate Mara), pilot Rick Martinez, flight surgeon Chris Beck, and navigator Alex Vogel, meticulously collect samples before retreating to their habitat, the HAB. The situation takes a dire turn as a powerful storm approaches, prompting Commander Lewis to abort their mission. Despite Watney's pleas to wait out the storm, he becomes separated from the team when a satellite dish is torn loose during the chaos and strikes him, causing him to lose sight of his crew. With visibility rapidly decreasing, Lewis leads the remaining crew back to the Mars Ascent Vehicle (MAV), reluctantly leaving Watney behind, who they believe is dead.
On Earth, NASA Director Teddy Sanders (Jeff Daniels) holds a press conference announcing Watney's presumed death, which shocks the world. However, Watney subsequently awakens on Mars on Sol 21 after the storm. After enduring a painful injury from the broken antenna that struck him, he ingeniously plans to survive with the limited food supply left for the crew, purposing to grow three years' worth of food on a lifeless planet. Thankfully, Watney's expertise as a botanist provides him the skills necessary to cultivate potatoes in Martian soil using compost made from the crew's fecal matter.
Meanwhile, back at NASA, Sanders returns from a memorial service expressing admiration for Watney's spirit. However, he is hesitant to allocate resources to search for Watney's remains. In a twist of fortune, Mindy Park discovers signs of activity at the Ares III site in satellite imagery, leading to a revelation that Watney is alive. With renewed motivation, Watney sets about creating a reliable food source and attempting to communicate with NASA by salvaging a long-dormant Pathfinder probe. He successfully establishes a connection that allows him to send messages back home, where NASA scrambles to decode his signals.
As Watney's plight gains global attention, the crew aboard the Hermes flies back toward Earth, kept unaware of Watney's survival until their flight director delivers the shocking news. Overcome with guilt, they learn that they have not only lost a friend but have also risked his life due to NASA's decision to withhold the truth. While Watney continues to fight to survive, unexpected mishaps challenge his survival, including a catastrophic failure of the habitat’s airlock that leads to further complications for his potato crop.
NASA's attempts to resupply him face hurdles, and in an act of international collaboration, the Chinese Space Agency offers assistance, allowing Rich Purnell, an eccentric yet brilliant astrodynamicist, to devise a daring plan that could potentially save Watney. Ultimately, the crew of the Hermes decides to go back for their stranded comrade, disregarding their orders. They take control of the ship, turning their mission into a personal rescue effort.
After months of struggle, Watney prepares for his daunting journey to reach the Ares IV MAV, relying on perseverance and unexpected ingenuity. His countdown to rescue is fraught with despair, uncertainty, and the harsh Martian environment. The climax unfolds as the crew of Hermes re-approaches Mars, witnessing Watney in a tense but emotional climax where the rescue operation hinges on meticulous precision and quick thinking. The world collectively holds its breath as the crew finally reunites with Watney, who has endured nearly a year of isolation and hardship.
Back on Earth, as a symbol of resilience and hope, Watney takes on the role of an instructor for new astronauts, sharing his hard-won wisdom from Mars. He emphasizes the importance of problem-solving as a means to survival, forever changing the trajectory of his life and the lives of those who dare to explore beyond our planet. As the credits roll, viewers are treated to glimpses of the characters' lives years later, highlighting their journeys as they witness the launch of the Ares V mission, a testament to human tenacity and exploration.
