In 1950 a number of Hollywood screenwriters, including Dalton Trumbo, were sentenced to almost a year's imprisonment for contempt of Congress. Their 'crime' was a failure to answer questions from the House Un-American Activities Committee about their involvement with the Communist Party, which in the paranoid atmosphere of the early Cold War was seen as threatening to undermine the United States through subversive movies. Following their release, the writers were placed on a blacklist, which meant no major studio would employ them.

How far those who led the attacks on 'reds' in Hollywood actually believed their own propaganda is a complex question, and one that Trumbo doesn't seek to explore. Rather, the film seeks to use Trumbo's story as an American allegory in which commitment to liberty triumphs and Trumbo, through grit, sheer talent, and the support of a loving family, emerges victorious, resuscitated by the industry which had helped bring him down.