9 (Elijah Wood) awakens one day, finding himself in a post-apocalyptic world, where all of the humans are gone. All that are left is a small community of others like him, including the imperious 1 (Christopher Plummer), the warrior-like 7 (Jennifer Connelly), and the one eyed sidekick 5 (John C. Reilly). While their group is small and relatively safe in hiding, 9 convinces the group to fight in order to survive. Their enemies: large machines that seem almost unbeatable. In order to win the fight, they must also discover why the machines are attacking in the first place. Will their risks pay off, and will they ultimately find a way to save civilization and life as they know it?