Sammy Fabelman (Gabriel LaBelle) lives with his family in New Jersey in the 1950s. His father Burt (Paul Dano) is a very motivated and hard-working computer engineer and his mother Mitzi (Michelle Williams) would have liked to become a pianist, but had decided to have children.
Since Sammy was taken by his parents to the movie "The Greatest Show on Earth" he is fascinated by the world of moving pictures.
He begins to re-enact a scene from the film that moved him so much and to film it with his father's 8mm camera and quickly his hobby of filmmaking develops further and further. Sammy is constantly faced with new obstacles and problems, but one thing remains constant: his passion for film.