The story unfolds in Coalwood, West Virginia, during the year 1957, where the local coal mine stands as the primary source of employment. Most men in the town are laborers at the mine, including John Hickam, played by Chris Cooper, who is the mine superintendent. John cherishes his work and has hopes that his sons, Jim and Homer—the latter portrayed by Jake Gyllenhaal—will follow in his footsteps. However, when it seems Jim is on the verge of receiving a college football scholarship, the burden of fulfilling John's aspirations weighs on Homer, much to the concern of his mother, Elsie.
In October, the launch of Sputnik 1 by the Soviet Union sends ripples through Coalwood. The townsfolk gather to watch the satellite cross the night sky, igniting a sense of wonder in Homer. Driven by his desire for a future beyond the confines of his hometown, he embarks on a quest to create his own rockets to enter a science fair. Initially ridiculed by his family and classmates, especially when he partners with Quentin Wilson, the school’s math whiz, Homer remains undeterred. Alongside friends Roy Lee Cooke and Sherman O'Dell, and with essential guidance from their science teacher, Miss Riley, they plunge into their newfound passion. Although their early attempts at launching rockets meet with failure, they begin to innovate with different fuels and designs. Their progress garners attention, leading to an article in the local newspaper.
However, their excitement soon turns into trouble when they are accused of igniting a forest fire with one of their malfunctioning rockets. After being released from police custody by John, Homer witnesses a distressing scene where Roy Lee is assaulted by his stepfather. John's heroic intervention reveals a deeper connection to Roy's father, exemplifying the support and care he offers to his employees. Unfortunately, the unraveling support from his father—coupled with the boys' prior arrests—dampens their spirits, causing them to abandon their rocketry dreams.
The turning point arrives after a mine disaster injures John while he valiantly saves several men but results in the tragic death of a colleague. Homer's life shifts as he drops out of high school to help provide for his family while John recuperates. Yet, buoyed by inspiration from a rocket science book gifted by Miss Riley, Homer learns to calculate a rocket's trajectory, only to discover that their unrecovered rocket couldn't have caused the fire. This revelation emboldens him and Quentin to track down the missing rocket, ultimately identifying the actual cause of the fire as a flare from a nearby airfield.
Upon returning to school, they resume their rocket-making endeavors, leading to their victory at a school science fair. Their triumph earns Homer an opportunity to compete at the national science fair in Indianapolis, Indiana. Tensions rise as John faces a near-violent confrontation linked to the fallout from a past threat made on Roy Lee's stepfather. After a heated argument with Homer escalates, the young man's frustrations boil over, prompting him to leave home in search of his own path.
At the prestigious national competition, Homer's exhibit garners much acclaim, but setbacks arise when someone steals his essential supplies. In desperation, he reaches out to his mother, Elsie, who pushes John to support their son, leading to a pivotal moment where he relents. With community backing, Homer ultimately secures the top prize at the fair, attracting multiple college scholarship offers. He even receives congratulations from his idol, Dr. Wernher von Braun, though he only realizes who it was after the fact.
When Homer returns to Coalwood as a celebrated figure, he visits Miss Riley, who is now gravely ill. He shares the news of his victory, and her heartfelt response is a touching moment between them. The film culminates in the launch of their largest rocket, the Miss Riley, with John finally stepping up to honor the occasion by pressing the launch button. As the rocket ascends, the camera captures the awe from various perspectives among the townsfolk, culminating with John placing a supportive hand on Homer's shoulder, signifying a moment of reconciliation and pride.
The narrative closes with a series of vignettes, including scenes from a Space Shuttle launch and nostalgic home movies of the characters, offering a glimpse into their futures, reflecting the enduring impact of their experiences.
