Matthew Collings argues that Impressionism is the single most important thing to happen to modern art, and that today's avant-garde exists only because of it. He builds the case around four painters, Courbet, Manet, Monet, and Cezanne, tracing how their lives and their canvases push each other forward across two hours. Collings breaks down the actual mechanics of the style: the raw strength of color, the flattened picture plane, the patterned brushwork, and the choice to paint ordinary life, cafes, riverbanks, haystacks, with what he calls startling truth rather than idealized polish. He also takes on the contemporary art world's snobbery toward Impressionism head-on, making the case that the movement's rejection of academic painting is the direct ancestor of everything the avant-garde later claimed as its own territory. The film moves between the paintings themselves and the circumstances that produced them, treating Impressionism less as wallpaper-friendly prettiness and more as a genuine rupture in how art could look and what it could show.