The 400 Blows

Antoine is a young boy in his early teens who has difficulties both at school and at home. His teacher singles him out for criticism and punishment, while his mother is cold and demanding, and frequently argues with her husband (Antoine's stepfather). The family is financially insecure, and Antoine must sleep in a sleeping bag on a cot crammed next to the back entrance to the apartment. Also, to make things worse, Antoine soon discovers that his mother is having an affair with a co-worker.

At school, Antoine is punished for the smallest of incidents, which escalate into more significant offenses. When the boys in his class pass around a risque picture, Antoine is the one who must take the blame. He is put in the corner as punishment, and passes the time there by writing a poem about the teacher, whom the children call "Sourpuss," on the classroom wall. He is reprimanded for his cheek and for defacing the school. Feeling contempt toward his schoolmaster and toward school in general, Antoine skips school one day. When asked where he had been the next day, his response is that his mother had died. He is punished again for his lie and his parents come to school to address the problem. His mother arrives distraught at the news, wondering why Antoine chose to kill her off in his story. The two have a poor connection, and she refuses to show him affection until after she discovers he found out about her affair. She promises to give him money if his grades go up, but to keep this deal a secret from his stepfather. It is implied that he must also keep her affair a secret too as a part of the deal. His mother also tries to spoil him by taking him to the movies.

Antoine engages in a childish mischief, often at the instigation of his friend René, but is caught and punished after each incident. He eventually steals a typewriter from his stepfather's workplace, planning to pawn it, but Antoine and René are unsuccessful in their attempt to pawn the typewriter. When Antoine visits the office to return it he is apprehended by the concierge; his stepfather turns him in to the police.

After his arrest, Antoine's parents place him with the investigating magistrate, saying that he is incorrigible. Antoine's mother requests only that Antoine be sent to a work camp by the sea, as he has never seen the ocean before. After some time in a juvenile detention center Antoine is indeed sent on to a work camp near the sea.

During a session with the psychiatrist at the detention center, Antoine reveals that he had spent most of his childhood living with his grandmother. His own mother had not wanted to take care of him. In fact, she had not wanted a child at all, and had planned to have an abortion.

Antoine eventually escapes from the work camp and runs toward the sea. Once Antoine reaches the shoreline of the sea, the film concludes with the camera zooming in and then freezing on Antoine's face (which seems to gaze into the audience).