In 1988 Chile, the military dictatorship of General Augusto Pinochet is forced to hold a national plebiscite on whether he should extend his rule for another eight years. The "Yes" campaign supports Pinochet's continuation, while the newly-formed opposition "No" campaign seeks to end his rule. René Saavedra, a talented but apolitical advertising executive, is approached to spearhead the "No" campaign's efforts. Despite his initial reluctance and personal risks, René eventually agrees and begins to craft a marketing strategy that focuses on creating a hopeful and optimistic vision for Chile’s future, tapping into his innovative advertising skills.

As René and his team work tirelessly, they face harassment and intimidation from the government, as well as internal conflicts from the fractured opposition about the tone and content of their campaign. The "No" team decides to use a positive and creative approach with slogans, jingles, and television spots designed to resonate emotionally with the populace. Their unorthodox campaign generates significant public attention and discourse, setting the stage for a historic moment in Chile's political landscape.