This film traces the adventure of a group of young painters who, in 1874, launched an aesthetic in total rupture with the historical painting in force in the official Salons. Inspired by the Realist School of Barbizon of Corot, Rousseau, Millet and Daubigny, this new generation is called Courbet, Pissarro, Jongkind, Renoir, Bazille, Cézanne, Caillebotte, Berthe Morisot and Claude Monet, their leader. "The Impressionist scandal" explains the distrust of the public and of critics towards this "revolutionary" painting which calls into question the way of seeing forms and light. Thanks to the unwavering support of the art dealer Paul Durand-Ruel, these works eventually established themselves and, thirty years later, entered national museums. Based on period documents, this abundant and documented film draws the trajectory of this popular movement which was at the origin of modern art.