Dalton Trumbo, a successful Hollywood screenwriter in the 1940s, is targeted during the Red Scare for his membership in the Communist Party. Called before the House Un-American Activities Committee, he refuses to testify and is subsequently blacklisted, alongside other Hollywood professionals accused of subversive activities. As a result, Trumbo serves time in prison for contempt of Congress and struggles to find work upon his release. His career and personal life face severe setbacks, but he remains determined to continue writing.

To circumvent the blacklist, Trumbo adopts pseudonyms and secretly crafts scripts for low-budget and acclaimed films alike. His relentless work ethic and talent earn him two Academy Awards under assumed names, inciting tension within the industry and scrutiny from both his allies and adversaries. His clandestine efforts gradually expose the injustice of the blacklist, leading to increasing support for blacklisted writers and artists. This period marks a significant chapter in Hollywood history, underscoring themes of freedom, perseverance, and the high cost of standing up for one’s beliefs.