The film opens in 1947, featuring Dalton Trumbo (Bryan Cranston) comfortably writing a script in his bathtub, an image that serves as a juxtaposition to the turbulent times ahead. An acclaimed screenwriter in Hollywood, Trumbo soon finds himself on set for a film adaptation of his work. At a subsequent party, he mingles with fellow actor Edward G. Robinson (Michael Stuhlbarg). The plot thickens as Trumbo visits a cinema and watches a reel where gossip columnist Hedda Hopper (Helen Mirren) publicly labels him and others in the industry as Communists, alluding to the formation of the House Un-American Activities Committee (HUAC) to investigate such claims. Following the screening, a patron recognizes Trumbo and angrily throws soda at him, marking the beginning of his troubles.
Later, at his ranch, his young daughter Niki inquires if her father is a Communist. Trumbo reassures her that wanting a better government is not criminal, using a poignant analogy about sharing lunch to illustrate his values. He convenes with Arlen Hird (Louis C.K.) and Robinson to discuss the rising paranoia being fueled by Congress. At a Motion Picture Alliance meeting, John Wayne delivers a harshly critical speech against Communism, and a confrontation ensues when Trumbo counters Wayne’s condescending remarks, pointing out that while he served in the military, Wayne only played soldier onscreen. Hedda Hopper observes this heated exchange, promising to report on it.
Visiting MGM Studios, Trumbo meets with the illustrious Louis B. Mayer, who advises him that his contract is making him the highest-paid writer in Hollywood, yet warns him against further negative press from Hopper. Trumbo is soon surrounded by friends and family celebrating his lucrative contract when an unexpected guest delivers a subpoena, branding him and his peers as threats to democracy. Amid a flurry of emotional exchanges, the Hollywood Ten decide to answer questions in the hearings vaguely, fearing potential contempt charges but established in their belief of eventual vindication from the Supreme Court.
The hearings take their toll, with Trumbo facing intense scrutiny as he stands against the Committee’s questioning, maintaining his innocence despite the tumult. The reality sets in when Trumbo confronts the fact that the Hollywood Ten are found guilty of contempt, leaving him on the brink of financial ruin after the annulment of his lucrative contract. Undeterred, Trumbo continues writing, disguising his work under pseudonyms—like Ian McLellan Hunter—to keep his craft alive. Soon enough, he finds success with the screenplay for Roman Holiday, a significant commercial hit, only to learn that the shifting tides in the Supreme Court could jeopardize his appeal efforts against the contempt charges.
As Trumbo begins serving his sentence, he encounters fellow prisoners, including J. Parnell Thomas, a senator implicated in his harsh treatment, fueling his sense of irony at the situation. Back in Hollywood, Edward G. Robinson finds himself obliged to name names, including Trumbo's, in a desperate bid for self-preservation. Despite the internal struggles, Trumbo keeps producing scripts and his family hatches a plan to continue his work covertly.
As time passes and Trumbo completes his year-long sentence, the changes around him are palpable. He strives to reconnect with his family, grappling with the emotional disconnection that developed during his incarceration. With the political climate still oppressing dissent, Trumbo’s family helps him navigate the complexities of the blacklisting, working tirelessly to establish a new normal until tragedy strikes with the death of Arlen.
However, as Spartacus takes shape with Trumbo's undeniable signature behind the script, the shadows of the blacklist loom larger than ever. In the end, when his identity as Robert Rich is revealed at the Oscars, the public narrative begins to shift against the blacklisting, lending strength to Trumbo’s voice as he stands resolute.
By the film's conclusion, we witness a powerful reflection on the broader impact of the blacklist era. Dalton Trumbo receives recognition in his twilight years, expressing a deep awareness that the tumultuous time affected not only individual careers but the humanity of all involved, ultimately serving as a call for compassion and understanding in the face of oppression.
