The film opens on a herd of white sheep, with one black sheep, crowding together as they make their way forward toward a pen. This image is juxtaposed with that of the factory workers piled together, getting off the subway and making their way to the factory. They all rush to punch in as the President of the Electro Steel Corp. sits in his office, putting together a puzzle and reading the cartoon section of the paper. The President next inspects his factory floor through a closed circuit television. As he send orders to speed up Section 5 we are introduced to The Tramp tightening bolts on the assembly line, and repeatedly falling behind but doing his best to catch up. The Tramp is briefly relieved and as he walks away from the assembly line he twitches as if he’s still turning bolts on the line. He tries to take a break to have a smoke in the bathroom, but just as he’s beginning to relax for a moment the President appears on a massive screen on the wall of the bathroom and yells at him to get back to work.
An inventor and two salesmen come to the factory to try to sell the President a Feeding Machine, which feeds the workers while they work, eliminating the need for a lunch hour. The President decides to try it out on The Tramp, but the machine malfunctions and slaps the Tramp around, feeds him bolts, and pies him in the face. None of the salesmen, nor the President, seem to care about the Tramp at all, and the President only turns down the machine because it is not practical, not because it is dangerous. The workers go back to the assembly line after lunch and the President again increases the speed of Section 5. The Tramp, obsessed with tightening each bolt as he gradually falls behind and moves down the line trying to catch up to bolts he missed, jumps onto the assembly line and is pulled into the gears of the machine. Once he is pulled out it becomes clear that he has suffered a nervous breakdown, and he runs around the factory trying to twist anything that remotely resembles a bolt with his wrench (including his co-worker’s nose and nipples and the buttons on the secretary’s skirt). He leaves the factory, and is chased by a policeman after trying to tighten the buttons on a woman’s blouse. He runs back into the factory to escape the policeman, being sure to punch in his time card when he returns, and nearly causes a riot at the factory as he runs around messing with machines, before he is finally arrested and sent to a hospital.
After being cured of his nervous breakdown, The Tramp leaves the hospital to begin his life anew. He’s told to take it easy and avoid excitement. Very shortly after being released, however, he is arrested as a communist leader for accidentally stumbling into a worker’s march. At prison, the Tramp accidentally eats and snorts a large quantity of cocaine that another prisoner had smuggled in. While on cocaine, the Tramp stops an escape by his cellmate and two other prisoners, and is rewarded by the warden and prison guards with special treatment (a private cell, modern comforts, a daily newspaper). Meanwhile, we are introduced to The Gamin, a poor young girl with an unemployed single father, who lives near the docks and steals bananas to feed herself and her family. She also gives some to other poor children in similar circumstances.
While The Tramp is reading in the newspaper about terrible things outside of the prison walls (unemployment, riots, etc.) he is called to the Warden’s office and informed that he is free to go. He asks if he can stay in jail longer, but the Warden laughs it off and gives him a letter of recommendation to find a job. When he leaves he is able to get work in a boatyard based on the Sheriff’s referral, but he accidentally sends the boat they are building off into the sea after a few minutes and is fired. Meanwhile, the Gamin’s father is killed during a protest, and her sisters are taken off to an orphanage but she escapes the cruel child welfare officers and wanders the city alone. She tries to steal a loaf of bread, but crashes into the Tramp, who is rounding a corner, and is caught by a policeman. The Tramp tries to take the blame for the stolen bread, but a nosy passerby and the store owner make it clear that the Gamin was the thief and have her arrested. Next, in an effort to get arrested and return to the safety of jail, The Tramp eats a massive meal in a cafeteria, and calls a police officer inside while explaining that he cannot pay. The policeman arrests him for stealing the meal and puts him in the back of a police wagon, where The Gamin soon joins him. After a minute, however, the Gamin attacks one of the officers in the van police officer and she and the Tramp are able to escape.
They walk through the city, come to a suburban area, and sit down on the grass outside of a house. As Chaplin describes how nice it would be to live in a house like the one behind them, a fantasy sequence shows him and the Gamin living together in comfortable bliss, with plenty to eat. In this dream, everything comes easily: a cow comes to the door when he calls and delivers milk without needing to be milked, and grapes and oranges grow in through the windows and doorways. The fantasy is interrupted when the Gamin tells him that she is hungry, and soon after a policeman approaches from behind them and they run off. While passing a department store, they find out that the night watchman has broken his leg, and the Gamin urges the Tramp to apply for the job. He uses his letter of reference from the Sheriff and gets the job.
Once the doors of the department store are locked up for the night, the Tramp and the Gamin explore the store. They feed themselves at the cafe and visit the toy section to rollerblade. The Tramp blindfolds himself while roller skating to show off, and nearly falls off the edge of the fourth floor because there is no railing. The Tramp puts The Gamin to bed on the fifth floor where the bedroom displays are set up and goes downstairs to do his rounds. We then see that three men have broken into the department store, but the Tramp does not notice them until it is too late. As the men take him hostage, they accidentally shoot a hole in a barrel of whiskey, in front of the Tramp but tell him that he cannot move, so he gets incredibly drunk as the alcohol pours into his mouth. We later find out that one of the burglars is the former factory worker who worked beside the Tramp on the assembly line. They tell him they aren’t burglars, they’re just hungry, and the drunken Tramp drinks with them and lets them go about their business. He is found sleeping under a fabric display the next morning and is once again arrested.
After the Tramp is released from jail, the Gamin brings him to a home that she has found for them. It is a small shack that is constantly falling apart and hurting the Tramp in some way (beams collapse on his head, chairs and tables collapse under him) but the Tramp tells her he loves it anyway. Reading the newspaper the next day, the Tramp discovers that the factory is reopening and runs there to find a job. He is one of very few that gets hired, and his job is to assist the engineer in repairing the machines, but repeatedly messes up the engineer’s work by accident. Eventually he gets the engineer stuck in the machine (though it is not directly his fault), and the machine shuts off the power for lunch before the Tramp can get him out, so the Tramp tries to feed the engineer while he’s stuck. Just when the lunch break ends and he gets the engineer out of machine, the workers decide to go on strike again and he has to leave the factory. While leaving, he accidentally hits a policeman in the head with a brick (by stepping on a plank with a brick resting on the other end, sending it flying through the air) and is arrested.
While the Tramp is in jail, the Gamin dances in the street and is hired by a cafe owner to dance at his cafe. She is successful and is able to get the Tramp a job as a singing waiter when he is released from jail. Meanwhile, the child welfare officers who first tried to take the Gamin under their charge get a warrant for her arrest and begin to search for her. In the cafe, the Tramp struggles with his serving job, and gets in a lot of trouble with the manager. He is told that he needs to do an amazing job singing to make up for it, but as he tries to rehearse he keeps forgetting the lines. The Gamin writes the words on his cuff for him, which helps, but when he goes out to perform he sends his cuffs flying off during the opening dance. He performs the song anyway, singing gibberish but dancing and acting out the lines, and gets a standing ovation. The owner offers him a steady job, but just as the Gamin heads out to the stage to do her dance, the juvenile officers appear to take away her away. The Tramp helps her escape and they run away. The next morning they sit on the side of a deserted street outside of the city, and the Gamin breaks down into tears, ready to give up on trying to find a better life. The Tramp convinces her to “buck up” and keep trying, and the two walk off into the sunrise, smiling.
