In 1952, a Jewish couple, Burt Fabelman and Mitzi Fabelman, introduce their young son Sammy to the magic of cinema by taking him to see The Greatest Show on Earth, directed by the legendary Cecil B. DeMille. Captivated yet haunted by a dramatic train crash scene, Sammy's fascination leads him to ask for a model train for Hanukkah. However, his desire quickly turns into a troublesome moment when he crashes the expensive toy, exclaiming that he “has to see them crash.” Recognizing the emotional turmoil behind his actions, Mitzi determines to help her son process his feelings by allowing him to film a re-creation of the crash using her husband's Super 8 camera.
This marks the beginning of Sammy’s journey into filmmaking, as he turns the camera on his sisters, Reggie and Natalie, creating a series of homemade productions. When Burt secures a new job in Phoenix, Arizona, the family embarks on a new chapter, accompanied by Burt's friend Bennie Loewy, affectionately referred to as "Uncle" Bennie. As Sammy navigates his teenage years, he begins involving his local Boy Scout troop in his films, demonstrating a knack for creativity that earns him praise from his father, even though Burt prefers him to pursue a more stable career.
Tragedy soon strikes the family with the death of Mitzi’s mother, Tina, leaving Mitzi emotionally overwhelmed. In an effort to cheer her up, Burt surprises Sammy with an editing machine on the condition that he edits their recent vacation footage. This project becomes a challenge for Sammy, as he discovers uncomfortable moments between Mitzi and Bennie, leading him to set aside his original footage after showcasing a more subdued version to his family, earning adoration from his mother.
However, tensions escalate when Sammy confronts the complexities surrounding his mother’s feelings for Bennie. Their family dynamics are further challenged with Burt’s job opportunity from IBM, requiring a move to California that does not sit well with Mitzi. Meanwhile, Sammy faces bullying at school, particularly from Logan and Chad, forcing him to wrestle with his identity and place within his new environment.
In a moment of emotional strife, Mitzi decides to adopt a monkey, symbolizing her fragile state of mind amid parental strife. As the family settles into their new home, Mitzi and Burt announce their divorce, profoundly impacting the children. In the wake of these changes, Sammy continues to pursue filmmaking, completing a project set for prom night. He expresses his aspirations for Hollywood to his date, Monica, only to find their relationship strained when she doubts his passion.
After a public confrontation with Logan, a moment of mutual understanding unfolds, allowing Sammy and Logan to reconcile. The next morning, an enlightening conversation with his mother reinforces the importance of following his aspirations in filmmaking. Fast forward a year, Sammy navigates life with his father, while Mitzi and the girls embrace a new chapter with Bennie in Arizona.
Despite challenges, Sammy receives a glimmer of hope when he connects with a CBS network executive, leading to an exciting opportunity in the world of television. His journey takes a fortuitous turn as he encounters the esteemed director John Ford, who shares invaluable filmmaking tips, leaving Sammy beaming with ambition and excitement for the promising path that lies ahead.
