Set in southwest France during 1962, this film narrates the coming-of-age journey of three friends: François Forestier, Maïté Alvarez, and Serge Bartolo. François, a reserved young man from a lower-middle-class family, is diligently pursuing his baccalaureate at a boarding school. His close bond with Maïté, whose mother Madame Alvarez is a French teacher at the school, allows them to engage in deep conversations about movies and literature. It's important to note that both Mme Alvarez and Maïté hold communist ideologies.
The film opens with François and Maïté attending the wedding of Pierre Bartolo, a former student of Mme Alvarez. During this event, they are introduced to Serge, the groom's brother and François's classmate, whom François perceives as somewhat dim-witted. Serge's family hails from Italy, and amidst the celebrations, Pierre seeks Mme Alvarez's assistance in avoiding military service in Algeria, which she declines.
As the story unfolds, we meet Henri Mariani, an Algerian-born French exile who is older than the boys due to his previous failures in school. A passionate supporter of the OAS (Organisation de l'armée secrète), Henri is preoccupied with the Algerian conflict. One evening, a significant turning point arises when Serge visits François in the dormitory, leading to an unexpected sexual encounter between them. They subsequently decide to aid one another in their respective academic strengths—François in French and Serge in Mathematics—to achieve their baccalaureate.
François begins to explore his homosexuality, forging a profound attraction to Serge, which he confides in Maïté. She reassures him that their friendship is paramount, irrespective of his romantic inclinations. Later, François and Henri engage in a poignant discussion about their fears, highlighting Henri's past struggles with depression following his father's death.
Tragedy strikes when Pierre dies while serving in the Algerian military, resulting in Maïté's mother experiencing a breakdown after her failure to aid him. Following the funeral, Maïté attempts to console Serge as he expresses his newfound affection for her, though she yearns for independence and maturity.
In a heated moment, Serge voices his disdain for Henri, blaming him for his brother's demise, which ultimately ignites a conflict between them. Injured while trying to break up the altercation, François is later confronted by Henri, who asserts that he believed Serge could relate to the pain of loss, urging him to embrace his true self.
François praises Henri, which repulses Maïté. She accuses him of merely wanting to be intimate with Henri, to which François candidly agrees, feeling burdened by his desires. Mme Alvarez's replacement, Monsieur Morelli, teaches a French class where they examine "The Oak and the Reed," a fable by Aesop. He extends help to Henri in academics, who reluctantly accepts after initially declining.
As Serge withdraws from school, François visits him and learns of Serge's intentions to marry his brother's widow, despite lacking love for her. Their escapades lead them to Toulouse, where Serge succumbs to heavy drinking.
After an OAS leader receives a life sentence, Henri, disillusioned, decides to quit school. A chance encounter with Maïté at a communist party gathering illuminates their oppositional beliefs and inadvertently spurs an emotional connection between them, leading to shared intimacy.
As exams approach, François, Maïté, and Serge plan a day at the river. In a moment of vulnerability, François seeks advice from Monsieur Cassagne regarding his love life, but finds him unhelpful. Tensions arise when Serge confronts Maïté about their lack of alone time, which she deflects, revealing her fears about intimacy.
Ultimately, as François and Serge bond in the water, Henri confesses his feelings for Maïté, resulting in a passionate encounter that deepens their relationship. However, after their intimate night together, Maïté suggests that love alone should not dictate their future, ultimately opting to join François and Serge as they return to the school, marking the end of this profound exploration of youth, love, and self-discovery.
