Nicolas, 13 years old, lives in a suburb north of Paris with his mother, a cleaning lady, and his older sister, a cashier in a supermarket. Left to his own devices, he and his friends have created a fearless gang that does not hesitate to travel to the capital to commit petty theft. The young boy, who attends a special education section, does not expect much from school. Everything changes with the arrival of a new teacher, who immediately seduces some of the students, including Nicolas, whom the young woman does not hesitate to welcome into her home to bring him up to speed. Nicolas makes lightning progress. But his momentum is broken by an event as painful as it is unexpected.