Franck and Christine are barely twenty years old; they live together, take the same theater lessons together, and are together chosen to play the leading roles in Sartre's "Les Mains sales". Franck is madly in love with her. Karl is still a high school student; he hardly sees his mother, absorbed by her gallery, her social events and her lovers, but he obtains from her all the money he can wish for. The big business of his life is Marc, who, older, lives in a loft and runs a clothes stand at the Flea Market with his father. Together they go to the Bains Douches, dance there frantically, and Karl admires the way Marc falls the girls. To be even closer, he introduces her to a classy friend, Sophie, who falls madly in love with all the confidence of her sixteen years. She gives herself to Marc, but very quickly discovers that she is not essential to him. At the Bains Douches, all three meet Franck, Christine and their inseparable Betti, and Marc and Christine immediately catch their eyes; they have appointments, and live locked in their passion. At the theater, Franck collapses; Sophie cries and discovers that she is pregnant; Karl tries in vain to see Marc. But cultural differences are stronger than passion and Christine leaves him. Marc then comes to make a scandal on the stage in full representation. Mad with pain, he leaves behind the wheel of his car to jump into the water.