The plot of "Modern Times" follows The Tramp through a series of misfortunes that satirize industrial society. After a frantic nervous breakdown on the assembly line, where he comically tries to tighten bolts on everything in sight, he is sent to a hospital. Upon release, he innocently picks up a red flag that has fallen off a truck, only to find himself at the head of a communist demonstration, leading to his first of several arrests. In jail, he accidentally ingests smuggled cocaine, which leads to a delirious episode where he single-handedly foils a jailbreak, earning him a pardon he doesn't want.
Outside, he meets the Gamin, an orphan fleeing the authorities after stealing bread. They dream of a suburban life together. The Tramp gets a job as a night watchman at a department store but is fired and jailed again after a drunken encounter with burglars who turn out to be his old factory co-workers. Later, he gets a job as a mechanic's assistant, but a strike breaks out, and he is arrested again for accidentally hitting a policeman with a brick.
The climax sees the Gamin get a job as a dancer in a café, and she secures The Tramp a position as a singing waiter. He becomes a sensational hit with an improvised nonsense song after losing his lyrics. Just as they seem to have found stability, juvenile welfare officers arrive to arrest the Gamin. They are forced to flee once more. The hidden meaning that becomes clear is that the system itself is the antagonist; there is no single villain to defeat. Every attempt to join society on its terms—through labor, lawfulness, or art—is ultimately rejected. Their only path to survival is to remain outside of it. The ending, where they walk down the road, is not a resolution but an acceptance of their status as perpetual outsiders, finding solace and strength only in each other.